Improved Weight Lifting System and Device for Fixing Positions of Weights on Bars

ABSTRACT

A barbell system for enhancing weight lifting exercises is described. The barbell system includes an elongated barbell comprising a first end and a second end. Weights are provided for placing symmetrically on the first end and the second end. A locking device is provided for securing the weights to the bar wherein the locking device has a split collar capable of receiving the elongated bar therein; and a locking device capable of drawing the split collar into engaging relationship with the elongate barbell.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to pending U.S. Provisional Patent Application No. 61/967,014 filed Mar. 7, 2014, which is incorporated herein by reference.

FIELD OF INVENTION

The instant invention is related to an improved barbell system and more particularly to an improved device for securing weights onto a barbell of a barbell system. More particularly, the present invention is related to a barbell system comprising a flexible barbell and to a locking device which secures weights on the barbell system.

Power is the maximum amount of work that can be performed in the minimal amount of time. It is somewhat based on strength but has elements of speed of motion. Power is the foundation of athletic performance in most sports.

Traditional barbells, which are relatively rigid, are well known and widely used to train athletes. Certain exercises are performed which are designed to increase the strength of the athlete. While effective at increasing strength, traditional barbells are not effective at increasing power. An experienced lifter can easily make every repetition look identical to the last and they are trained to accomplish consistency in their training. Lifting a traditional barbell involves lifting “dead weight”. The traditional bar has very little flex and once a lifter finds “the groove” on any particular lift the traditional bar can be moved in a very predictable manner. Unfortunately, this does not always translate well into sport performance, especially in contact sports, where a dead weight does not effectively mimic action.

Vladimir Zatsiorsky, in his book “Science and Practice of Strength Training”, identifies a phenomenon called “Explosive Strength Deficit (ESD)” which can limit an athlete's ability to generate power despite his or her ability to generate absolute strength. The reason for this is that there is a relationship between strength and time. Maximum strength (force development) takes more time than most sport performances allow. The window of opportunity to generate force during real sport performance is small. For example, the length of time a sprinter's foot is in contact with the ground during a race is very short and it is during this short time that maximum strength needs to be applied. Similarly, a batter must move a bat from near rest to full speed quickly to achieve maximum strength at the point in time when the bat impacts the ball. During many sport performance events there is insufficient time to generate maximum strength within the time allowed to exert maximum force or power.

There has been a long standing desire to convert the potential for generating force (otherwise known as strength) and train our bodies to generate as much of that force or power as possible. There has also been a long standing desire to reduce explosive strength deficit of athletes by being able to generate the greatest portion of absolute strength within the time limits of a particular sport performance. To accomplish this the neuromuscular system must be trained, which means applying resistance in a very sport specific manner that allows the athlete to mirror the speed of movement as much as possible. Many training systems are designed to do this such as plyometric training, weighted implements and through the use of lifting submaximal weights very rapidly. These methods have their limitations. Lifting weights rapidly or using weighted implements often requires deceleration at the end of the motion which does not often carry over to the sport performance. Plyometrics often use body weight and are therefore limited by this as a resistance exercise. Adding weight to the body using weighted vests can circumvent this problem, but increases the risk of injury to the athlete.

The use of flexible barbells has greatly enhanced the art of strength training, and particularly strength training using free weights. There are many types of devices that are used in the art to be affixed around all or a portion of the circumference of a bar for the purpose of holding the disc weights in position and preventing them from sliding off of the bar should the bar be titled. Many of these devices are difficult to use, time consuming to use and lack long term durability. Some closure devices currently in the market include Lock Jaw Elite® collars which are made from molded plastic materials and subject to breaking from repeated opening and closing, Olympic spring collars by USA Sports and other manufacturers, Pro-Lock® collars, Muscle Clamps® collar, Mega Grip® Heavy Duty collars and Bull Dog® collars. These are all designed for rigid bars and therefore fail with a flexible bar since the directions of force with a flexible bar is unique and the material of construction limits the compressive force which can be applied. Conventional bar collars therefore either fail to adequately fix the weights in position on a flexible bar or they damage the material of construction leading to catastrophic failure.

The present invention greatly enhances the training regimen of athletes by converting strength of the muscles to power by neuromuscular training.

BRIEF SUMMARY

It is an object of the invention to provide an improved system, and method, for training the neuromuscular system of athletes to enhance sports performance.

It is another object to provide a system, and method, for training athletes to increase power.

These and other embodiments, as will be realized, are provided in a flexible barbell for enhancing weight lifting exercises and a locking device for securing the weights to the flexible barbell. The flexible barbell has an elongated shape, comprising ends, which is capable of being grasped by at least one hand. Weights are attached to the shape near the ends. The shape bends relative to a tangent to the center in response to the center of the flexible barbell being moved.

Yet another embodiment is provided in a barbell system for enhancing weight lifting exercises. The barbell system includes an elongated barbell comprising a first end and a second end. Weights are provided for placing symmetrically on the first end and the second end. A locking device is provided for securing the weights to the bar wherein the locking device has a split collar capable of receiving the elongated bar therein; and a locking device capable of drawing the split collar into engaging relationship with the elongate barbell.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of an embodiment of the invention.

FIG. 2 is a partial cross-sectional schematic representation of an embodiment of the invention.

FIG. 3 is a schematic representation of an embodiment of the invention.

FIG. 4 is a schematic representation of an embodiment of the invention.

FIG. 5 is a diagrammatic representation of an embodiment of the invention.

FIG. 6 is a perspective schematic view of an embodiment of the invention..

FIG. 7 is an isolated schematic view of a component of the invention.

FIG. 8 is an isolated schematic view of a component of the invention.

FIG. 9 is a side schematic view of an embodiment of the invention.

FIGS. 10A and 10B are perspective schematic views of an embodiment of the invention.

DESCRIPTION

The present invention is related to a weight lifting system. More specifically, the present invention is related to locking device for fixing the position of disc weights to an elongated, preferably flexible, barbell to limit the ability of a disc weight, or weights, to move parallel to the barbell. The locking device is positioned and fixed, in one embodiment, between the end of the bar and the outside surface of the outermost disc weight to secure the weights against a mechanical stop that is an integral part of the elongated device or against a second locking device described herein or a device of conventional design. The locking device is easily and quickly affixed to the barbell thereby providing the user with a securely attached weight, or stack of weights, that allows the barbell to function properly without risk of weights sliding from the barbell. The locking device has a toughness and durability suitable for use in a gym or strength and conditioning facility. While the locking device is particularly suitable for use with a flexible barbell it can be demonstrated with, and used with, conventional rigid barbells.

The instant invention is related to a flexible barbell which can be grasped by at least one hand and designed to be used by weightlifters building muscular force strength, muscular velocity strength, muscular endurance strength, increase the speed of muscle contraction, enhance the ability of the various supporting muscles, ligaments and tendons to work together more effectively and to train the sensory receptors (proprioceptors) in the muscles and tendons to improve the ability of the individual to be more aware of the relative position of the various muscle groups which interact in performing a movement thereby resulting in an enhanced ability to perform movements more effectively.

The invention will be described with reference to the various figures which are included for the purposes of describing the invention without limit thereto. Throughout the invention similar elements will be numbered accordingly.

An embodiment of the invention will be described with reference to FIG. 1. In FIG. 1 a system for neuromuscular training is illustrated in schematic view. A flexible barbell system, generally represented at 10, is illustrated with weights, 14, thereon. A locking device, 60, which will be described further herein, is preferably provided to prohibit weights from sliding off of the flexible barbell during use. The flexible barbell, 12, preferably comprises a surface treatment, 18, which will be described in more detail herein. A timing device, 20, is preferred to assist the athlete in the timing of the lifting exercise to insure that the movement of the flexible barbell during a lift is in concert with the flexing of the flexible barbell as will be more fully described herein. The timing device may be a metronome or any device which can alert to a preset repeating pattern of time intervals.

An embodiment of the invention will be described with reference to FIG. 2. In FIG. 2 a flexible barbell, 12, is illustrated in partial cross-sectional view. The flexible barbell comprises an elongated shape, 22, such as a tube which is sealed on either end by a closure such as an end cap or end plug, 24. The closure prohibits flexible bars, 26, or flexible rods, 27, inside the elongated shape of the flexible barbell from exiting the elongated shape. At least a portion of the elongated shape is preferably covered with a surface treatment, 28, which may be an applied coating or a wrap. An applied coating is a material which is applied as a flowing chemical such as by a dip, spray or spread-on material and a wrap is a material which is adhesively applied. The surface treatment is preferred to improve the grip, aesthetics, durability, stiffness or friction of the exterior of the elongated shape. Indicia, 30, along the elongated shape are preferred. The indicia allow the separation of the weights or the separation of the hands to be placed at a specific distance repeatedly and accurately and insure the center of the flexible barbell is indicated to avoid lateral weight asymmetry. A hitch pin, 32, which is received by a void, 34, may be used as an added precaution to insure that the weights do not slide off of the ends of the flexible barbell in the unlikely event of a locking device failure.

An embodiment of the invention will be described with reference to FIG. 3. In FIG. 3 a lifter, 40, is illustrated fully extended. The flexible barbell, 10, with weights, 14, is shown bent from linearity. The deviation from linearity will be described with reference to

FIG. 5. In FIG. 5, a tangent to the center, T, is defined at the center of the flexible barbell. The deviation is measured as the distance the end of the bar is from the tangent, indicated as D. Alternatively, the deviation can be measured as the acute angle α, between the tangent to the center, T, and an end tangent ET at the weights. It would be realized that the deviation can be measured in any plane. It is preferred that the static deviation from linearity, D, is at least 12.7 mm (0.5 inches) and more preferably at least 63.5 mm (2.5 inches) to no more than about a 45 degree acute angle α. As would be realized, the very large value of the distance, D, and large angle, α, particularly relative to a rigid barbell, causes the weights to be persuaded towards the locking device during use. Traditional lock collars either failed to be adequately secured to the barbell or tended to damage the flexible components of the bar with a potential for catastrophic failure.

In a particularly preferred embodiment the movement rate for a single back and forth motion is 0.3-1.5 M (1-5 ft.)/second and as the lifter reverses direction the momentum of the weight is moving in the opposite direction. If the deviation from linearity is less than about 12.7 mm the flexibility of the flexible barbell is insufficient for light weights such as no more than 11 Kg (25 lbs). For heavier weights, such as above about 11 Kg (25 lbs) with a deviation from linearity of less than 63.5 mm (2.5 inches) the flexibility of the flexible barbell is insufficient to move in response to the lift. If the static deviation from linearity is more than about a 45 degree acute angle a the flexible barbell will probably deflect too much during use.

An embodiment of the invention will be described with reference to FIGS. 4A and 4B. In FIG. 4A the lifter, 40, is moving from a squatted position to a standing position in the direction of arrow 44 while the initial force of the weights is in the direction of arrows 46. The lifting motion is referred to in the art as the concentric phase. As the lifter reaches the full extension and reverses direction as indicated by arrow 48 in FIG. 4B the momentum of the weights is in the direction of arrows 50. The lowering motion is referred to in the art as the eccentric phase. To optimize the results the momentum is contrary to the movement of the lifter each time the direction of movement changes. As would be realized from further discussions herein the oscillatory amplitude of the flexible barbell is higher than the oscillatory amplitude of the lifter. In one embodiment the lifter will pause for a time to allow the weights to approach the end of their oscillatory cycle, represented by D in FIG. 5, prior to reversing direction.

The invention is not intended to be limited to the embodiments described; rather, this detailed description is included to enable any person skilled in the art to produce and to use effectively a locking device as a component of a weight lifting system which significantly enhances the reliability and effectiveness of the weight lifting system by providing the user with a locking device that is easy to use, and a tough and durable component of a weight lifting system. This locking device is able to be used with elongated bars of different diameters. This closure device is able to be used with rigid elongated ‘steel’ bars or flexible composite bars.

A locking device is illustrated in perspective view in FIG. 6 without the barbell. The split collar, 61, is illustrated in isolated view in FIG. 7 and one embodiment of the closure mechanism is illustrated in isolated view in FIG. 8. The locking device is illustrated in FIG. 9 as engaged with a barbell. The locking device comprises a split collar, 61, which can be placed on the barbell either by receiving the end of the barbell in the central void, 68, or by separating the split collar at the split, 62, to the extent necessary to pass the bar laterally there through. The split collar has a contoured surface, 66, on the inside thereof to provide resistance against moving once tightly engaged with the barbell. As will be realized from further discussion the rigidity of the split collar is defined such that adequate pressure can be exerted without damage to the barbell. The split collar preferably has raised edges, 70, preferably on an outside diameter edge, which inhibits the strap, 64, which is at least partially wrapped around the split collar from moving laterally. Mounting voids, 72, on either side of the split, 62, allow the closure mechanism to be secured to the split collar such as by threaded members, 74, or the functional equivalent thereto. Molded-in metal screw inserts may be included in the mounting voids wherein the screw inserts receive threaded members. A particularly preferred closure mechanism is a strap, 64, and more particularly, a strap with a Velcro™ closure. The strap comprises an attachment, 76, which secures a ring, 78, therein. The shape may be the shape of the capital letter “D” or it may be substantially rectangular. Substantially rectangular is preferred since the pressure across the ring is more evenly distributed with a substantially rectangular ring. The ring is secured to one end of the strap by the attachment with the other end being unattached. The strap is preferable secured to the split collar by the aforementioned threaded members in the aforementioned mounting voids thereby insuring the strap remains in a preferred orientation bound by the raised edges within the recess formed there between. The free end of the strap can be free from the ring thereby allowing the barbell to pass through the split if so desired. When deployed the free end of the strap is inserted through the ring and wrapped back in opposite rotation such that mating hook and loop closure elements, 80, also known in the art as Velcro™, can reversibly engage as illustrated in FIG. 9. As would be realized from the description herein one would place the locking device on the barbell, 12, with the strap inserted through the ring. The strap would then be drawn tight and manipulated such that the closure elements engage thereby securing the locking device onto the barbell and securing the weights on the barbell.

An embodiment of the invention is illustrated in partial schematic view in FIGS. 10A and 10B. In FIG. 10A, a closure element, 84, is illustrated in perspective view in a partially unlatched arrangement and in FIG. 10B the closure element is fully latched. The closure element comprises a fixed attachment, 86, preferably fixed to the split collar such as by threaded members at least into the mounting voids as discussed above. A buckle assembly, 88, is secured to the split ring opposite the split. The buckle assembly includes a ring, 90, pivotally attached to a latch, 92, wherein the latch is also pivotally attached to a base, 94. The base is attached to the split collar, such as by threaded members, into the mounting voids as discussed above. The employ the closure element the locking device is placed around the barbell and the latch is rotated towards the fixed attachment thereby allowing the ring to engage with the fixed attachment. The latch is then rotated away from the fixed attachment thereby drawing the split ring together at the split which secures the barbell in the central void of the locking device as set forth above.

It is preferable that the locking device accept a barbell with a diameter of about 48 mm (1.89 inches) to about 53.3 mm (2.1 inches) as this is the optimal range of elongated flexible bars manufactured from Schedule 40 tubing with a diameter of about 48.3 mm (1.90 inches) to the approximate 50.3 mm (1.98 inches) diameter and corresponds to the approximate size of a standard Olympic barbell. A preferred material of construction for the split collar is a thermoplastic rubber with a flexibility such that a person of normal strength is able to pull open the split collar to position the split collar onto the elongated, preferably flexible, bar. The width of the closure device is preferably at least 25.4 mm (1 inch) to about 76.2 mm (3 inches) with about 50 mm (2 inches) being suitable for demonstration of the invention. Below about 25.4 mm there is insufficient surface area on the inner diameter (ID) for sufficient grip on the barbell. Above about 76.2 mm the space occupied by the closure device limits the number of weight disk which can be employed on the barbell. The outside diameter (OD) of the split collar is a function of the thickness with an OD of about 63 mm being the minimal size given the typical barbell sizes and material thickness requirement. An OD above about 75 mm provides no additional benefit and the additional material cost is prohibitive. An OD of about 68.27 mm (2.688 inches) has proven to be optimal for demonstration of the invention. The inside diameter of the closure device is preferably slightly smaller than the OD of the barbell thereby insuring that the slit is not completely closed when the locking device is fully engaged. An ID of about 45 to about 48 mm is optimal with an ID of about 46.38 mm (1.826 inches) being suitable for demonstration of the invention. The wall thickness is dependent on the material of construction with a wall thickness of about 8 to about 12 mm being preferable. A wall thickness of about 10.9 mm (0.431 inches) is suitable for demonstration of the invention. The separation of the slit, when engaged, is preferably greater than zero since this insures maximum grip. The separation of the slit, when engaged, is preferably not large since an increase in gap size decreases the surface area available for engagement with the barbell when engaged. A gap of at least about 2 mm to no more than about 5 mm is preferred with a gap, when engaged, of about 3.7 mm (0.146 inches) being suitable for demonstration of the invention.

The inside surface of the split collar has contour to increase the gripping ability of the barbell. The shape of the contour is not particularly limiting, however, crosshatched lines covering at least a portion of the ID surface, and preferably the entire ID surface, are preferred due to manufacturing convenience and effectiveness. The contour preferably is formed with a contour depth, measured from highest peak to lowest valley on the inner surface, of at least about 0.1 mm to preferably no more than about 0.5 mm with these crosshatched lines being indentations molded into the closure device ID surface. Below a depth of about 0.1 mm the contour has insufficient ability to form a sufficient grip and above about 0.5 min the effectiveness also decreases. A contour depth of about 0.3 mm (0.012 inches) is suitable for demonstration of the invention. When used with a flexible elongated bar such as a Tsunami Bar® LIGHT bar, the gripping to the surface is further enhanced due to the fact that the surface of the Tsunami Bar® LIGHT is made from a thermoplastic rubber material which allows the crosshatched ID surface of the closure device, which is also a thermoplastic rubber material, to press into the OD surface of the Tsunami Bar® LIGHT which creates better gripping ability than when the closure device is used with a steel elongated bar although the gripping ability of the closure device to the OD of a steel elongated bar is enhanced due to the crosshatched pattern of the ID of the closure device coupled with the compressibility of the thermoplastic rubber material.

The raised edge of the split collar has a sufficient height to prohibit the strap from sliding laterally off of the split collar. The raised edge can be formed by a molding process or material can be removed with the raised edge being maintained. The height of the raised edge is preferable at least 1 mm to no more than about 4 mm. Below about 1 mm the height is insufficient to inhibit the strap from lateral movement over the raised edge. Above about 4 mm the raised edge becomes a nuisance to the user. A raised edge of about about 2 mm (0.080 inches) above the OD is suitable for demonstration of the invention. With an approximately 50.8 mm (2 inches) wide closure device the indented surface area bound by the raised edge is capable of accepting a nylon strap centered around the outside of the split collar and the nylon strap is prevented from moving side-to-side due to the raised edge at both outer edges of the closure device thereby allowing the closure device to be used more efficiently and effectively as the user wraps the nylon strap around the split collar. Further, the nylon strap is preferably attached in two places as discussed above using threaded members, or the equivalent thereto.

The strap is preferably a nylon strap mating Velcro™ sections positioned along the surface of the nylon strap such that the mating sections adhere to each other when pressed together as discussed above.

It is a principal objective of this invention to provide an improved weight lifting system comprising several different diameters of weight lifting bars which are elongated devices that accept disc weights being loaded onto each end of the bar and a tough, durable and easy to use locking devices to fix the position and/or limit the movement of the disc weights that are placed on the elongated device with the locking device able to be used with more than one diameter bar.

In one embodiment the locking device fits a standard or flexible barbell with an OD ranging from 48 mm (1.89 inches) to 53 mm (2.1 inches) and more preferably about 51 mm (2.00 inches). In one embodiment the locking device fits 48.3 mm (1.90 inches) OD or 49.2 mm (1.9375 inches) OD solid round rod. Some of the elongated bars used in weight lifting are: Olympic Weight Bars, Tsunami Bars®, Olympic Curl Bars, Specialty bars such as Olympic Fat Bars, Safety Squat Bars, Rackable Cambered Bars, Swiss Bar, Strongman implements such as Logs, Farmers Walk Handles, and Yokes. In one embodiment the flexible barbells comprise a component that is an integral part of the bar and limits the distance that the disc weight can be pushed onto the bar. Alternatively, the weights can be limited by a device such as a spring loaded device persuaded to engage the barbell or a locking device as described herein. A vital component of all lifting systems is a device which is normally positioned in contact with the outside surface of the outermost disc weight on each end of the barbell for the purpose of keeping the weights from sliding off of the end of the bar especially should the person using the bar allow the bar to tilt which positions the weights to slid off or in the case of the Tsunami Bar® barbells to prevent the disc weights from sliding off when as the bar bends up and down. Four locking devices, as described herein, with one on either side of each weight or weight stack is particularly preferred.

It is an additional objective of this invention to provide an improved weight lifting system that remains consistent in its ability to hold the disc weights in position by providing excellent gripping ability of an improved locking device and prevents the disc weights from sliding off should the barbell be tilted during use. Further, the operating conditions in a typical weight room, gym or strength and conditioning facility subjects the weight lifting systems to abuse. An additional objective of this invention is to provide a weight lifting system with an improved closure device to fix the position of the disc weights on the elongated bar that is abuse resistant and which incorporates features into the weight lifting system that allows the weight lifting system, in conjunction with the locking device, to fix the position of the disc weights on the elongated bar such that a high level of consistency is achieved from a functional standpoint by insuring that the weight lifting system can be used effectively and safely over a long period of time.

In one embodiment the split collar is made from a thermoplastic rubber compound with a durometer of about 65 to 100 Shore A with about 85 Shore A being optimal. Within this range the thermoplastic rubber material is sufficiently pliable to provide a tight engagement with the barbell yet not so hard as to potentially damage the flexible barbell. Furthermore, this range would be flexible enough to expand for placing around the bar laterally yet still have sufficient strength to insure that breaking of the material is very unlikely and the closure mechanism maintains the collar in a firmly closed positioned against the outside surface of the barbell and is highly abuse resistant and replaceable. For example, in one embodiment straps are used which can be replaced by removing screws, such as four (4) screws, and replace the old strap with a new strap. An additional objective of this invention is to provide a weight lifting system with an improved locking device that incorporates into the design of the closure device features that allow the locking device to be put between 2 disc weights that are already positioned on the bar without having to take the disc weights off of the barbell.

The disclosed weight lifting system is preferably durable construction including the use of tough elastomeric materials used to construct the locking device coupled with a closure attachment that allows the user to achieve a consistent and highly reliable level of gripping ability to keep disc weights in place time-after-time. The weight lifting system is significantly enhanced through the synergistic combination of functional design features of the molded closure device coupled with the closure attachment portion of the closure device and the materials used to construct the closure device and the means by which the closure attachment device is attached to the molded closure device.

In use, the flexible bars and rods in the elongated shape provide strength to the flexible barbell and are chosen to achieve the proper amount of flexibility for the weight range and exercise of choice as more fully described herein. Bars with a rectangular cross-section are most preferred but rods find use both with and without bars where increase in bending stiffness is required. Flexible rectangular bars rotate within the elongated shape such that the largest face of the rectangle is perpendicular to the direction of force applied to the flexible barbell.

The form of the weights used with the instant invention is not particularly limited. Olympic style and standard disc weights, weighted bags such as sand filled bags, chains and/or other weighted devices affixed to each end of the flexible barbell can be used. The weight is preferably in the form of disc weights where the flexible barbell is inserted through a hole in the center of the disc weights. Iron plates or discs, are widely used with weight lifting. The plates typically range in weight from about 1.1 Kg (2.5 lbs) to about 45 Kg (100 lbs). Plates typically have a centrally located hole. Plates with a hole having an approximate diameter of 51 mm (2 inches) are typically referred to as Olympic disc weights and plates with holes having an approximate diameter of 25.4 mm (1 inch) are typically referred to as standard disc weights. Sand bags, such as those available from Rae Crowther Co. of Rock Hill, S.C. are filled with sand and typically weight from about 35 lbs to about 55 lbs. Kettlebells typically range from about 5 lbs to about 80 lbs. Kettlebells feature an approximate round steel ball with integral curved handle allowing the kettlebell to be grasped by one or both hands. Kettlebells may be suspended from the flexible barbell by sliding the handle onto an end of the flexible barbell and securing the kettlebell to the flexible barbell by a locking device. Metal chains may be suspended from each end of the flexible barbell by a hook and secured by a locking device. Chains and hooks are available from ‘TOTAL STRENGTH AND SPEED, Inc.’ of West Columbia, S.C.

The flexible barbell bends up and down at its ends in response to the up and down movements of the body using traditional weightlifting movements. One such weightlifting movement is a back squat wherein the center of the flexible barbell is positioned behind the user's neck which allows the user to condition and train the affected muscles in a beneficial way and in ways that are not possible when using traditional steel barbells where the degree of bend during use is minimal due to the very rigid material's properties of steel. The effects of traditional weightlifting movements is further enhanced when the user moves their body or parts of their body such as their arms, shoulders, or legs in a up and down or back and forth manner which allows the ends of the flexible barbell to move or oscillate in an up and down or back and forth manner in trailing rhythm to the movements of the user's body and in response to the forces transmitted to the flexible barbell by the user as the exercise movement is performed. This oscillatory movement of the ends of the flexible barbell causes stresses (or forces) to be transmitted to the user's muscles, tendons and joints plus conditioning and training of the sensory receptors in the user's muscles, tendons and joints such that beneficial results occur for the user. Some of the beneficial results are the ability of the muscles to contract faster which allows for greater speed of movement which can give the user greater power in the use of their body with particular emphasis on the use of the arms, shoulders, legs and core.

The oscillating movement of the ends of the flexible barbell allows the user to perform isokinetic oscillatory exercise as a result of the ends of the flexible barbell moving up and down or back and forth depending on the methods that the user will be practicing for strengthening and conditioning of the user's muscles, tendons and joints. Further, the timing and efficiency of the concentric and eccentric muscle contractions in body parts performing the exercise will be enhanced through proper practice of the methods of use of the flexible barbell. In addition, when placing the flexible barbell behind the neck, such as in performing a back squat, the loads of the flexible barbell are transferred in a safer manner to the outer sections of the body in the shoulder area and over the hips and legs as opposed to being transmitted along the length of the spine in the center of the body as occurs with the use of a rigid steel barbell. This present invention will define several methods of using the flexible barbell in performing exercises that will be beneficial for the user and will be readily understood by professionals in the Strength and Conditioning field.

The methods of exercise are dependent upon the proper flexibility and strength characteristics of the flexible barbell in combination with the placement on the flexible barbell of the selected disc weights or other weight forms to allow the user to develop a rhythmic movement that is in harmony with the up and down or back and forth movement of the ends of the flexible barbell in response to the forces imparted to the center section of the flexible barbell by the movement(s) of the user. An apparatus construction that allows the ends of the flexible barbell, with weights affixed, to oscillate with appropriate oscillation amplitude and oscillation frequency to permit effective use of the flexible barbell by the weightlifter is desired herein. U.S. Pat. No. 7,951,051 entitled Variable Resistant Exercise Device is incorporated herein by reference.

The stiffness of a shape constructed of a particular material is defined as:

Stiffness=E*I

wherein E is the flexural modulus of the material and I is the moment of inertia of the shape geometry.

In addition to the stiffness of the flexible barbell, the oscillation frequency and oscillation amplitude are influenced by multiple factors. For a composite, the type of fiber used as the reinforcement in the flexible bar is a factor with oscillating frequency and oscillation amplitude with glass fibers being the preferred fiber. The diameter of the flexible barbell is a factor in oscillating frequency and oscillation amplitude with a diameter from 25.4 mm (1 inch) to about 63.5 mm (2.5 inches) being the preferred range. The method of obtaining the required flexural strength is a factor in oscillating frequency and oscillation amplitude with the use of fiber reinforced composite shapes in combination with an extruded thermoplastic tube being the preferred materials. The length of the flexible barbell is a factor in oscillating frequency and oscillation amplitude with a length from 5 to 8 feet being the preferred range. The use of functional closures on the ends of the flexible barbell to insure safe and efficient use of the flexible barbell influences oscillating frequency and oscillation amplitude to a lesser degree.

The model also describes the dual action of the flexible barbell, which adds an element of stabilization. Unlike conventional stabilizer exercises like the Swiss ball, in which the training surface is unstable, the flexible barbell provides an unstable resistance or “live weight”. But, the flexible barbell does more than target stabilizer muscle groups. It allows the lifter to generate maximal forces with submaximal weights loaded on the flexible barbell.

The flexible barbell generates forces based on two primary factors. One factor is flexible barbell frequency, which is based on the flexibility of the flexible barbell, the length of the flexible barbell, where the weights are placed on the flexible barbell and the amount of weight being used. The flexibility of the flexible barbell is constant and cannot be manipulated by the lifter. However, the other three variables can be manipulated. Another factor is user frequency, or force frequency, which is based on hand placement and the timing of the repetition frequency or how fast or slow the lifter moves the flexible barbell.

Each hand is preferably positioned on each side of the centerline of the flexible barbell at a distance from 20.3 cm (8 inches) to 61 cm (24 inches) with 21.6 cm (8.5 inches) to 24.1 cm (9.5 inches) being the most common position for the hands from the flexible barbell's centerline.

With the flexible barbell the forces generated by the flexible barbell, known as impulse forces, can be affected by the timing of the lift. Impulse forces are defined as how much force is needed to change the direction of the flexible barbell as it moves downward, in a given amount of time. Putting this into a simple formula:

Force×Time (impulse force)=Mass×change in velocity

In the flexible barbell lifting protocol this can be manipulated by setting the metronome at very specific lifting frequencies to fit the training goal. Decreasing the “time” factor in the above equation requires an increase in “force”, thus by increasing the frequency of the metronome can increase the amount of force needed to move the weight. The amount of force can be controlled by either speeding up the repetition frequency or slowing it down without ever having to change the weight on the flexible barbell. The stiffness (EI) of the flexible barbell with E=the elastic characteristics of the material used to construct the shapes used in the flexible barbell and I=the moment of inertia of the shapes used to construct the flexible barbell remains relatively constant under differing parameters such as changing the weight on each end of the flexible barbell.

The flexible barbell allows for minimal joint stress since the force needed to move the weight changes throughout the range of motion and is only maximal at predetermined points throughout the lift. The flexible barbell and a standard barbell have been compared using electromyography (EMG) to compare muscle activation in various lifts. These tests lead to the conclusions that the stabilizer muscles are 3 times more active using the flexible barbell properly in the bench press. The pectoral muscles and deltoid muscle groups were found to have a much greater EMG response in the deltoid groups. During a close grip bench press, in which the lifter stops the flexible barbell four inches from the chest and immediately presses the weight upward while the flexible barbell is still accelerating downward, the muscle activation was 20% greater than the same action using a standard barbell of the same weight. In other words, the muscle activation at the transition from down to up was much greater using the flexible barbell. Proper training is critical since the flexible barbell does all the work if the timing is not right.

Power, speed and agility can be improved using the flexible barbell. Many training systems use chains or rubber bands to increase resistance through the range of motion of many standard barbell lifts such as bench press and squats. The drawback of this method is that the weight decelerates from start to finish as the resistance increases. Deceleration is not representative of actual activities such as jumping, sprinting or throwing where follow through is critical to performance. The wave action of the flexible barbell maximizes force at a predetermined critical phase of the lift, but then decreases force to allow the athlete to accelerate.

Most lifts performed on a standard barbell can be adapted using the flexible barbell. However, to get the most out of the flexible barbell, it is not simply a matter of using it the same way as you would a standard barbell. An ideal system would allow for resistance to increase meeting the most critical phase of a given movement and then decrease to allow for full acceleration on the follow through. When used properly the flexible barbell does just that.

The flexible barbell employs two types of oscillations simultaneously. The lifter must time exertion based on the target adaptation which is dictated by the sport performance one is trying to train. As an example, in jumping there is a critical point in the range of motion in which maximum ground reaction forces must be generated to get maximum height. That point where the hips and knees are flexed and are about to extend explosively upward. The flexible barbell allows an athlete to initiate the jump as the flexible barbell is accelerating downward to hit that critical “sweet spot” in the jumping motion. The faster the flexible barbell accelerates downward, the greater the resistive forces at that point. But unlike conventional weights, once the maximal resistance is met, the momentum of the flexible barbell transitions to an upward acceleration allowing the athlete to move more rapidly on the follow through of the jump. Thus maximal resistance only occurs where it is needed.

The invention is not intended to be limited to the embodiments described; rather, this detailed description is included to enable any person skilled in the art to produce and to use effectively a flexible barbell such that the ends of the flexible barbell will bend in the downward direction when weighted devices are attached to each end of the flexible barbell and the flexible barbell is supported in the center section of the flexible barbell by a means such as the supporting brackets on a steel lifting frame or behind the neck and on the shoulders of a lifter which act on the center section of the bar to allow gravity to pull the ends of the flexible barbell in the downward direction. And the flexible barbell responds to forces that are applied to the center section of the flexible barbell with the weighted devices on the outside of the applied forces such that as the forces are applied in an up-and-down manner (as in a bench press starting with the flexible barbell on one's chest) or a down-and-up manner (as in a squat with the flexible barbell behind one's neck and the person starting from a standing position) or a forward-and-back manner (as in a Zercher Push Pull movement), by oscillation of the ends of the flexible barbell with the amplitude of oscillation of the ends of the flexible barbell proportional to the magnitude and speed and duration of the force applied to the center section of the flexible barbell with the person that is exerting the force in the center section of the flexible barbell controlling the oscillation amplitude of the ends of the flexible barbell by the timing of their application of force to the center section of the flexible barbell as the ends of the flexible barbell are oscillating up-and-down, by the force and speed that is exerted on the center section of the flexible barbell and any delays that the individual may insert into the movement or lifting routine to allow the oscillating ends of the flexible barbell to reach a different position before resuming the application of a force at a given speed to the center section of the flexible barbell.

A traditional steel barbell is very stiff and does not bend (nor is a steel barbell designed to bend) appreciably in performing the wide variety of exercises such as those using a flexible barbell with weights on each end such as bicep curls, military presses, barbell upright row, bench presses, barbell squats, deadlifts, or clean and jerks. When significant weights are placed on a steel barbell, the ends of the barbell will deflect downward slightly but a rhythmic oscillation of the ends of a steel barbell during use does not occur when using steel barbells in use today due to the stiffness of the steel barbells in use today. Traditional steel barbells are either approximately 7 feet or 8 feet in length although other lengths can be used. It has not been demonstrated to date to use a traditional steel barbell to produce a beneficial up and down oscillatory type of movement as can be performed with a flexible barbell as described in the various preferred embodiments of the present invention which have been constructed to give the strength and stiffness of the flexible barbell necessary to allow acceptable oscillatory amplitude and oscillatory frequency in conjunction with the movements of the user in performing the many weightlifting exercises using a flexible barbell with circular weights placed at each end of the flexible barbell. The person performing the exercises can position their hands so that one hand in on top of the other hand in the center of the flexible barbell, the two hands are side by side with the 2 thumbs or 2 index fingers touching in the center of the flexible barbell or with the hands spaced an equal distance apart from the center of the flexible barbell or using just one hand which is placed at the approximate center of the device. The flexible barbell can be positioned behind the neck and supported at the shoulder areas, in the cusp of the arms as in performing a Zercher push-pull or in other ways where the ends of the flexible barbell are able to respond to forces exerted on the center of the flexible barbell to produce acceptable oscillation amplitudes and oscillation frequencies for the weightlifting method practiced. This invention and methods of using the invention pertain to a flexible barbell and is hereinafter described in detail.

The flexible barbell allows the user to train and condition their muscles in more effective ways than using a traditional steel barbell which is very stiff. The lifting phase of an exercise movement is called the concentric phase. The lowering phase of an exercise movement is called the eccentric phase. A person can generally ‘lower’ about 40% more weight than they can ‘lift’. In the lifting phase of an exercise using a flexible barbell, the actual amount of weight that is felt by the person when starting the exercise movement, such as a deadlift, is less with a flexible barbell than with a steel barbell due to the fact that the flexible barbell bends in the center as the individual applies the initial upward force to the center of the flexible barbell with the weights outside the hand position towards the ends of the flexible barbell. Once the flexible barbell has bent to the point where the stiffness of the flexible barbell is sufficient to raise the weights off of the surface, then the full weight of the flexible barbell with weights will be transferred to the muscles of the user, but in a different and potentially more beneficial manner than with using a traditional steel bar. There is a lag or delay in the transfer of the full weight of the flexible barbell and weights to the user because the center portion of the flexible barbell bends first with less force required by the user until the ends of the flexible barbell have moved off of the surface and upward once the flexible barbell's strength and stiffness is able to overcome the downward weight of the circular weights at each end of the flexible barbell. The invention is not intended to be limited to the embodiments described; rather, this detailed description is included to enable any person skilled in the art to construct a flexible barbell and to perform weightlifting exercises following methods that will allow the movements of the user to interact with the responses of the flexible barbell to enable the exercises to be done in a beneficial manner.

The flexible barbell is made from special composite materials, which provides a unique training stimulus. The motion of the flexible barbell has been scientifically analyzed using high speed cameras and a computerized motion analysis. The data from this analysis was then used to develop a precise mathematical modeling of the motion of the flexible barbell. The mathematical model provides great insight into the forces generated when the flexible barbell is used in the proper fashion, depending on the lift performed. All standard Olympic lifts can be performed using the flexible barbell.

The elongated shape of the flexible barbell may have any suitable shape with a round or approximately round exterior to include an oval shape with many types of materials inserted to the center cavity of the device if the shape has a center cavity or materials placed or applied on or onto the outside of the device that makes contact with the person's hands as long as the shape exhibits that capability to flex adequately such that that shape does not crack, crimp or break in performing the various lifting procedures and the shape exhibits acceptable oscillation amplitude and oscillation frequency characteristics in performing at least one of the many lifting procedures used in the strength and conditioning of individuals.

The flexible barbell preferably has an approximately hollow round shape with a uniform wall thickness formed by the process of fixed length or continuous filament winding over a mandrel such as a round steel mandrel in which continuous fibers of glass, carbon, aramid, nylon or combinations of these are saturated with a liquid resin are wound around the mandrel at angles from the horizontal that can vary from zero degrees to 90 degree (i.e. 45 degrees, 75 degrees, etc.) with the normal practice being that the wind angles are balanced with an example being a balanced winding of fibers in a +/−45 degree from horizontal, or angles of wind that features more than one wind angle such as a combination of an approximately zero degree wind angle fibers for one or more layers with one or more layers of an approximately 90 degree wind angle, or a combination of wind angles such as +/−10 degrees combined with +/−75 degrees. The reason for multiple wind angles is to provide acceptable combination of hoop strength with longitudinal strength with the longitudinal component being the primary contributor of bending stiffness which affects the flexibility and the oscillation (frequency and amplitude of oscillation) characteristics of the flexible barbell. Use of a thermoset resin is preferred in filament winding products although a thermoplastic resin may be used.

Particularly preferred materials for the tube are polyvinyl chloride (PVC), polypropylene (PP), high density polyethylene (HDPE) and chlorinated polyvinyl chloride (CPVC).

The flexural modulus of the fiber reinforced resin shape can be measured using traditional testing methods. Below is an example of two (2) filament wound products that are manufactured on a continuous process with the benefit of a continuous process being that the mandrel can be a constant and consistent diameter the entire length of the filament wound part. This constant diameter along the length of a flexible barbell is desirable in that this insures that the bending characteristics on each side of the centerline of the flexible barbell are the same and that the disc weights used in the weighting industry will fit uniformly on each end of the flexible barbell.

Representative elongated shapes include a fiberglass pipe with OD from about 25.4 mm (1 inch) to 2″ with continuous strands of glass fiber in both the longitudinal direction, up to 15 degrees off of zero degrees direction, and hoop directional with angle of wound continuous strands of glass being between 90 degrees and 45 degrees from the longitudinal or zero degree direction provided by Ameron-Bonstrand of Burkburnett, Tex. as Series 2000 Fiberglass Pipe, product code FP163F. This tubular product is not tapered and has a consistent 51 mm (2 inch) nominal OD, 42.4 mm (1.67 inches) ID and consistent wall thickness.

Another representative elongated shape is provided by Glasforms, Inc. of San Jose, Calif. which is an epoxy resin tubing primarily for use with ‘Standard Weight Disc Plates’. The elongated shape is a filament wound epoxy resin tubing using continuous glass fibers as the reinforcement. The following products can be used for flexible bars using weights with a ‘hole’ with diameter of about 25.4 mm (1 inch). Model BW106500 has nominal 27.05 mm (1.065 inches) OD, 22.1 mm (0.872 inches) ID a wall thickness of 2.36 mm (0.093 inches) and is available in a length of 2.74 M (108 inches). Model BW106510 has nominal 27.05 mm (1.065 inches) OD, 27.05 mm (1.065 inches) ID a wall thickness of 2.36 mm (0.093 inches) and is available in a length of 2 M (79 inches). Model BW106520 has a nominal 27.05 mm (1.065 inches) OD, 27.05 mm (1.065 inches) ID a wall thickness of 2.36 mm (0.093 inches) and is available in a length of 1.52 M (59.75 inches). A particularly suitable elongated shape for demonstration of the invention is a 2.4 M (94⅜ inches) PVC schedule 40 extruded pipe manufactured by Silver-Line® Plastics Asheville, N.C. 28804 which has an approximate OD of 48.5 mm (1.91 inches) and an ID of 39.7 mm (1 9/16 inches); a 25.4 mm (1 inch) CPVC extruded pipe, 488 Kg/M² (100 psi) rated, manufactured by Silver-Line® PlasticsAshville, N.C. 28804 which has an inside diameter of approximately 22.2 mm (0.875 inches) and an OD of approximately 28.5 mm (1.125 inches) with lengths of 2.3 M (91.875 inches) or 2.34 M (92.1875 inches).

Particularly preferred elongated shapes feature the use of continuous glass or carbon fibers with defined layers of the continuous fibers being either in the longitudinal direction, zero degrees to the lengthwise direction, or hoop direction, approximate 90 degrees to the lengthwise direction with this angle capable of going down to 45 degrees.

Particularly preferred elongated shapes have an approximately hollow round shape with a uniform wall thickness and constant cross-section formed by the process of pultrusion in which continuous forms of reinforcing materials such as continuous fibers, glass, carbon, aramid, nylon, etc., continuous rolls of reinforcing mats or fabrics plus continuous rolls of materials such as surfacing veils of nylon or polyester fiber are wetted with a liquid thermoset or thermoplastic resin with the resulting wetted material system pulled through a shaping device and then into a curing die where the final shape of the end product is fixed either by cross-linking of the thermoset resin or cooling of the thermoplastic resin with the thermoplastic resin having been heated to a liquid state or a room temperature thermoplastic resin is used such a PVC plastisol. In some pultrusion processes the liquid resin is injected directly into the curing die to wet the reinforcements. The amount and orientation of the reinforcing materials is selected to give acceptable stiffness of the shape to be able to exhibit acceptable oscillatory frequency and oscillatory amplitude to function as a flexible barbell. The pultruded products are continuously pulled over a fixed mandrel and through a die which insures a fixed and consistent OD making pultruded round elongated shapes ideally suited as candidates for a flexible barbell with the selection of the appropriate reinforcing materials determining the elongated shape's flexibility and the oscillation frequency and amplitude which can be designed into the pultruded product to match the performance characteristics of the identified preferred embodiments. The focus of the pultruded flexible shapes will be the round elongated shapes with an OD of both 50.8 mm (2 inches) and 25.4 mm (1 inch) making them useable with existing disc weight which have an ID of either 50.8 mm (2 inches) or 25.4 mm (1 inch). A pultruded shape using a vinyl ester resin is preferred to insure the best long term flexural performance. Acceptable pultruded tubing can be purchased from Strongwell Corporation of Bristol, Va.

An approximately hollow round shape with a uniform wall thickness and constant cross-section formed by the process of extrusion augmented with pultrusion in which continuous forms of reinforcing materials such as continuous fibers (glass, carbon, aramid, nylon, etc.) are wetted with a liquid resin (a liquid PVC thermoplastic plastisol) with the resulting wetted materials or B-stage materials pulled into an extrusion machine in advance of the extrusion die with curing of wetted reinforcements and consolidation of the wetted reinforcement(s) with the melted PVC pellets occurring in the heated extrusion die chamber. An alternate method is to feed a fully or partially cured reinforced strand(s) into the extrusion dies chamber such that that the resin impregnated reinforcing strand(s) is surrounded by the melted thermoplastic resin. If the resin component of the reinforced strand is a PVC plastisol, then a degree of chemical bonding will occur and if the resin matrix is another resin such as a thermoset resin then the degree of chemical bonding will be less and primary bonding will be either mechanical and/or simple sticking of the thermoplastic extrusion resin to the surface of the fiber reinforced strand. In either of these methods the primary fiber direction is parallel to the lengthwise direction of the extruded round shape. Where the extrusion thermoplastic pellets are PVC and the resin used to wet the reinforcements is a PVC plastisol with the resulting shape cured in a heated die reference hereby is made to U.S. Pat. No. 6,955,735B2 issued Oct. 18, 2005. Resin selected from the group consisting of vinyl ester thermoset, isophthalic polyester thermoset, epoxy thermoset, polyurethane thermoset, polyvinyl chloride, polypropylene, high density polyethylene, thermoplastic rubber, and chlorinated polyvinyl chloride is particularly preferred.

The internal flexible bar can be a solid round shape with a constant OD or solid shape with a major and a minor axis with the two axis not of the same dimension made from such materials as composites which contain continuous reinforcing fibers and a suitable resin using the process of pultrusion, or a metallic shape made from a material like steel, spring steel, aluminum, etc. which has appropriate stiffness, flexibility and adequate flexural fatigue performance may be used as the primary material of construction or as a component of the construction of a flexible barbell and even to replace the external tubular shape. A 12.7 mm (0.5 inches) OD solid steel rod has a stiffness (E*I) of approximately 434,170 kG/M² (88,925 lbs-in²) and 3 fiberglass bars with each bar having dimensions of 31.75×9.52 mm (1.25×0.375 inches) together have a stiffness of about 483,360 Kg/M² (99,000 lbs-in²). Therefore the 12.7 mm (0.5 inches) solid steel rod would give similar bending characteristics to the three fiberglass bars although the oscillatory characteristics would be different but if acceptable, this steel rod could replace the three fiberglass bars. Three fiberglass bars fit nicely inside a 38.1 mm (1.5 inches) CPVC Schedule 40 tube whereas a 12.7 mm (0.5 inches) diameter steel rod would be very loose inside the 38.1 mm (1.5 inches) CPVC Schedule 40 tube and this would allow the CPVC tube to bend a greater distance before it had bent enough for the 12.7 mm (0.5 inches) diameter steel rod to take some of the load of the weight means attached at the ends of the flexible barbell. This would alter the oscillatory bending/flexing characteristics. The flexible barbells are preferably sized to accommodate standard Olympic iron disc weights with a hole in the center that is 50.8 mm (2 inches) in OD and the standard iron disc weights with a hold in the center that is 25.4 mm (1 inch) in OD. Other weights may be used such as sand bags, etc. and other iron disc weights with different diameter holes could be made to accommodate flexible barbells with different OD's but the practical range of OD's for iron disc weights is projected to be in the range of 12.7 mm (0.5 inches) to about 63.5 mm (2.5 inches). A solid fiberglass rod with a flexural modulus of about 29,294,566 Kg/M² (6,000,000 psi) and an outside diameter of 23.8 mm (0.9375 inches) has a stiffness (EI) of 1,110,249 Kg/M² (227,397 lbs-in²) which would enable this 23.8 mm (0.9375 inches) diameter rod to be used as a flexible barbell in a length of about 2.28 M (90 inches) by itself eliminating the need for a tube although this diameter bar would be used with standard disc weights that had a 25.4 mm (1 inch) diameter hole or the ends of this 23.8 mm (0.9375 inches) diameter shape could be retrofitted with a covering that would enable the use of Olympic size disc weights with 50.8 mm (2 inches) diameter holes, and this bar could be coated with a LineX XS-350 polyurea material in order to offer additional exterior protection.

Acceptable composite solid round pultruded shapes are available from Glasforms, Inc. of San Jose, Calif. Solid steel tubular shapes are available from a variety of sources such as Ryerson Inc. of Chicago, Ill. In addition to defining the stiffness of the flexible barbell, the minimum and maximum amount of weight that is placed on a flexible barbell is to be defined for each flexible bar construction.

A particularly suitable flexible bar is a fiberglass pultruded rectangular shape with dimensions of 6.35×19.05×2321 mm (0.25×0.75 wide×91.375 inches). The fiberglass shapes were manufactured by Trench Electric in Toronto, Canada. Two of the fiberglass rectangular shapes were inserted into the center cavity of a 25.4 mm (1 inch) CPVC extruded tube. This fiberglass rectangular shape has a flexural modulus of approximately 34-30 million Kg/M² (5-6 million psi). A material such as round 9.525 mm (0.375 inches) diameter foam backer tubing that is traditionally used as an insulation type of material to plug gaps around windows may be wrapped around the 25.4 mm (1 inch) CPVC extruded tube and secured at each end of the CPVC tube using a piece of duct tape. This wrapping of the 9.525 mm (0.375 inches) foam backer tubing takes up some space between the outside of the 25.4 mm (1 inch) CPVC tube and the inside diameter of the 38.1 mm (1.5 inches) diameter PVC schedule 40 tube into which the 25.4 mm (1 inch) CPVC tubing will be inserted. This foam backer material serves to dampen any noise from the movement of the CPVC tubing inside the PVC tubing.

It is particularly preferred to apply end caps or plugs to the end of the elongated shape for aesthetics and to prohibit the internal flexible bars from sliding out of the elongated shape. For example, 25.4 mm (1 inch) CPVC end caps can be affixed to each end of 25.4 mm (1 inch) CPVC extruded elongated shape. The 25.4 mm (1 inch) CPVC cap fits over an end of the 25.4 mm (1 inch) CPVC extruded pipe. A suitable end plug is a 38.1 mm (1.5 inches) plastic mechanical pipe plug from Oatey® of Cleveland, Ohio. The wing nut of the Oatey pipe plug adds about 20.64 mm (0.8125 inches) to the length of each end of the 38.1 mm (1.5 inches) PVC extruded tube.

It is preferable to add a surface treatment, such as a coating or a wrap, to the exterior of the elongated shape. A material suitable for demonstration of the invention is 3M Safety-Walk™ Anti Slip Tape in Grey color available from ACE hardware as code 64175. This tape contains a slip-resistant surface of a durable rubber-type material which is comfortable to the hands and allows the user to grip the surface of the flexible barbell plus the wrap increases the OD of the 38.1 mm (1.5 inches) PVC tube so that the circular barbell weights have a reduced tendency to slip on the surface of the barbell.

Additional apparatus constructions may be used as long as they provide the user with acceptable oscillation amplitudes and oscillation frequencies with weights affixed to each end of the flexible barbell as have been achieved with the above preferred embodiments in the performance of at least one lifting method. Speed of movement of the hands of the person doing the lifting in applying forces to the center of the flexible barbell in conjunction with the physical properties of the flexible barbell being used, the amount of weight on each end of the flexible barbell plus the length of the movement of applied forces. The length of the arm extension in performing a bench exercise determines the oscillation amplitude and oscillation frequencies of the flexible barbell during the use of the flexible barbell with one requirement being an acceptable perceived responsiveness of the flexible barbell. This is determined by the user of the flexible barbell.

A rate of movement of the hands of the individual that grasp the flexible barbell is preferably between 30.35 and 152 cm (1 and 5 feet) per second. An acceptable means for determining acceptability of alternative constructions is the stiffness of the flexible barbell. Stiffness is defined as the product of E (material modulus)×I (moment of inertia of the shape being used). An apparatus with an exterior circular shape is preferred but other shapes may be used as long as the shape exhibits acceptable oscillation amplitude and oscillation frequency.

Training with the flexible barbell provides the lifter with added safety and builds muscular force strength, muscular velocity strength, muscular endurance strength, increase the speed of muscle contraction, and enhances the ability of the various supporting muscles, ligaments and tendons to work together more effectively for potential enhancement of the affected movements by training the sensory receptors, or proprioceptors, in the muscles and tendons to be more aware of the relative position of the various muscles groups.

There are many lifting movements where the use of a flexible barbell can enhance the specific training. Most lifting movements using a flexible barbell are similar to the movements when using a standard steel barbell. Because the weights at or near the ends of the flexible barbell are moving in an oscillatory manner with an amplitude in response to the forces exerted by the lifter on the center section of the flexible barbell, the methods of using a flexible barbell effectively are different from the methods used when lifting with a steel barbell.

Resistance training falls into two primary categories: speed resistance training and force resistance training. In speed training the lifter will use a submaximal amount of weight and the muscle response and activation will be faster than in force training. In force training, the lifter will use maximal weight, consequently muscle activation will be slower than in speed training. Use of a flexible barbell permits new methods to be used to achieve maximum results surpassing the results that are achievable when using standard steel barbells.

The contraction of one's muscles, when they activate, are either eccentric or concentric contractions. The weights at the ends of a flexible barbell can move in the same and opposite direction from the direction of movement of either the arms or body of the lifter during both the eccentric and concentric contraction phase of muscle movement. Depending on the objectives of the training, the lifter, when the muscles are approaching the end of the eccentric contraction, can develop a timing response for the weights to fully bottom-out before engaging the muscles in the concentric contraction phase which is supported by ‘The Sliding-Filament Model of Muscular Contraction’ which is specific to Force training. This model was independently developed by Andrew F. Huxley and Rolf Niedergerke and by Hugh Huxley and Jean Hanson in 1954. The timing response is part of the new method in using the flexible barbell most effectively. Response timing, wherein the lifter waits for the weights to bottom-out, results in a new and novel method for lifters to perform. The lifter will want to wait until the weights bottom-out in order to allow the muscles to take the maximum load (Sliding-Filament Model) which will be greater than the total amount of weights placed on the ends of the flexible barbell due to the effects of momentum of the moving weights. And while the lifter is waiting for the ends of the flexible barbell to bottom-out the ancillary supporting muscles will be activated and conditioned as the lifter must control the movement of the flexible barbell. This method results in training focusing on building additional strength through Force training.

But the lifter can alter the above method and before the weights bottom-out in their movement, the lifter can begin the concentric phase of muscle contraction for Speed training. The lifter moves and pushes against a force that is increasing to the point where the weights bottom-out. This places an increasing stress on the skeletal muscular system. The focus of this type of ‘new and novel’ movement is to enhance the ability of the targeted muscles to ‘fire faster’ so the net result is the lifter's ability to move their hands and arms faster. This occurs with a football lineman who will keep their elbows in a bent position and their hands 6-8 inches away from their chest. Therefore, moving their hands and arms, using concentric muscle contractions to full extension that will make contact with the opposing player. A football player wants to be able to move the arms as fast as possible so he can be the first to make contact and gain an advantage over the opposing player. This ‘new’ speed training method trains the muscles to contract faster. The same principal applies to a lifter that would be performing squats in which the legs are bending at the knees vice the bending of the arms. As the legs bend downward in the squat the weights at the ends of the flexible barbell bend downward and when the lifter moves upward before the weights have bottomed-out for Speed training, the continued downward movement of the weights places increasing stress on the muscles of the legs, quads and hamstrings, resulting in training that will allow the muscles to ‘fire faster’ resulting the football player being able to extend their legs faster from a bent position enabling them to move their bodies faster and make contact with the opposing player quicker and with more ‘power’ with the combination of force and speed.

The lifting methods using a flexible barbell for the greatest benefit in developing muscle strength and power feature several common features. A basic feature in the majority of exercises using a flexible barbell is to challenge the muscles in a unique way during the eccentric phase of the exercise. Muscles can handle about 40% more weight during the eccentric phase of weightlifting than the concentric phase. During this phase, which is also called the negative phase, the weights at the ends of the flexible barbell will continue in a downward movement once the user has come to a stop due to the flexing of the flexible barbell and the momentum of the downward moving weight. This downward momentum of the downward moving weight places greater stress on the user's muscles during this eccentric movement. This flexibility is dramatically demonstrated when performing a squat with the flexible barbell behind and resting on the back of the user's neck. During the downward (or eccentric) movement of the user, the weight will continue moving downward as the user stops and reverses the movement direction to up. Then during the upward movement of the lifter, the weights at the end of the flexible barbell will change direction and the force of the flexing fiberglass bars will cause the weights to accelerate slightly in the upward direction. When the user is at the full upright position, the flexible barbell is still moving up which during this upward movement has slightly reduced the stress on the user during this lifting or concentric phase of the movement which is an enhancement due to the use of the flexible barbell given the fact that fatigue will set in more quickly during the concentric phase than the eccentric phase because the eccentric phase can handle almost 40% more weight than the concentric phase. And when the oscillation characteristics of the flexible barbell are in harmony with the up and down movement of the user during the squat exercise, the user is able to maintain a rhythm which results in more effective transfer of the forces encountered by the user during the exercise to the muscles resulting in better muscle conditioning, greater ability in training the muscles to fire more responsively or respond faster and more effectively during use and better conditioning due to greater loads being transferred to the muscles during the eccentric phase that is enabled through the use of a properly designed flexible barbell in combination with the correct amount and positioning of the circular weights. If an exercise can be performed at high enough frequency rate, then the ability to train the muscle, tendons and joint sensory receptors is made possible. A flexible barbell exercise where this is more applicable is a bench press with rapid up and down movement with the flexible barbell constructed to move up and down at a frequency that is in harmony with the up and down movement of the individual's arms. Other types of lifts to which this applies are the jump squat and split jump squat.

Another benefit to the weightlifter is the fact that because the flexible barbell bends in the center, the load of the flexible barbell is transferred to the lifter in a different manner than with a steel barbell. With the flexible barbell bending in the center, the loads in a back squat are transferred more to the sagittal planes of the body instead of the spinal column which decreases stress on the vertebrae with the loads transferred to the large shoulder muscles and the ankle, knee and hip joint which reduces the risk of a spinal injury and makes the training process safer and more effective for the lifter in pre, during and post competition. This will enable the lifter to train with greater velocity or speed due to using submaximal weight. By using submaximal weight the force-velocity relationship will be greater than with a steel barbell, and increase the amplitude and oscillatory factor which will stimulate to a higher level the neuromuscular system and increase the firing (contraction speed) of the muscle. This use of submaximal weight in combination with faster lifting movements is unique with a flexible barbell and not possible with a steel barbell as a steel barbell does not bend and does not allow for the momentum gain which occurs when the ends of the flexible barbell bends.

Using submaximal weight means using a weight which is roughly 60% or less of maximal weight, which gives the lifter the ability to apply more velocity to the lift. This enables the central nervous system to be more stimulated in a sense of firing (or contraction speed) the muscle. The rigid steel bar is great for developing force, or strength, but is difficult to use in a manner that the flexible barbell gives in the development of coordination, balance, rhythm, speed, plyometric and reversal movements. Because the ends of the flexible barbell move during the lifting movements, the athlete must concentrate on maintaining body balance and coordination of the various muscles that are being used, and this promotes better coordination among the various muscles and an increased ability to move the body in a more stable and balanced manner. Also, the athlete's sense of awareness, or proprioception, of the various parts of their body engaged in the lifting process is enhanced due to the conditioning of the muscles being used under the combination of the weight of the flexible barbell and weights on the flexible barbell plus the added velocity due to the movement of the ends of the flexible barbell. This promotes an ability for the athlete to use the various parts of their body and the muscles that move these body parts in a more effective manner.

The lifter lowers a steel bar to the chest and the steel barbell is rigid, in which case the lifter could possibly drop or bounce the steel barbell on the lifters chest resulting in possible injury. The flexible barbell bends in the middle thereby minimizing the chance of chest injury due to the weight shifting to the sagittal plane of the body moving the weight from the center of the chest area to the outside edges of the body. As the lifter unracks the weight, the ends of the flexible barbell bend downward and the flexible barbell begins oscillating which develops core and shoulder stability which is very beneficial in athletic competition. As the lifter lowers the weight they are able to work different movements with the flexible barbell. The first, being a normal lowering and pressing of the flexible barbell. The second is a more plyometric or reversing of the flexible barbell. As this lift is performed the greater the velocity and force that is applied by the lifter the greater the amplitude of the oscillating ends of the flexible barbell and the greater the neuromuscular development implications. This lowering of the weight using the above mentioned normal method and the alternative method of the lowering being a more plyometric or reversing can be applied to other methods of lifting such as a back squat wherein the legs are effecting the lowering of the body rather than the arms, and the rate of lowering and then raising up effects the amplitude of the oscillating ends of the flexible barbell. Also, at the down or up position, there can be a slight pause which affects the transfer of the weights to the muscles and joints of the body to allow the lifter to train effectively in a variety of ways.

Another benefit of the flexible barbell is the rehab methods of uses. These includes lifts that are loaded on the back such as a back squat, but not limited to the back that enables the lifter to rehab from hip, knee or ankle injuries/surgeries. This gives the lifter the ability to load sub-maximal weight that will enable them to develop coordination, balance, rhythm, and the ability to train the muscle to fire more effectively again through the proprioception process. This process enables the muscle to reverse or respond to the resistance that is applied through neuromuscular responses that train the muscles to perform or respond with greater accuracy, control and power during the rehab process.

Another significant aspect of the flexible barbell which alters the methods of lifting is the ability to move with the flexible barbell and not stay in a stationary position. For example the jump squat or the split jump squat. The flexible barbell moves with the body and deloads the stress off the spine due to the loading of the sagittal plane instead of the spine. The flexing up-and-down of the flexible barbell enables the athlete to move up and down, back and forth and side to side. During the flexing of the ends of the flexible barbell the weight is transferred to the supporting muscles in a softer and gradual manner as opposed to the instantaneous manner of a steel barbell. During this movement, the muscles that surround all the joints in which stress is being applied are working in a more conducive way that relates to athletic movement.

The athlete can use the flexible barbell for force training because of the ability to load heavy weight on the flexible barbell. The lifter or athlete can use the flexible barbell in a dynamic manner in which they are more focused on developing the central nervous system to train the muscles to fire more effectively. They can use the flexible barbell for balance and coordination purposes through the oscillating effect of the flexible barbell's movement. The lifter or athlete can use the flexible bar as a prehab or rehab tool to develop the muscles, the muscle attachments and the firing mechanisms that surround the joints being exercised. They can also use the flexible barbell in mobile capacity in which they move from a stationary position into a mobility action such as a jump squat. Their anaerobic capacity can be greatly enhanced due to the endless possibilities for altering the methods of lifting that the flexible barbell allows them to do.

Many athletes perform multi-joint movements when they compete. A flexible barbell allows the multiple joints to be developed in different and unique ways. For example the back squat allows the athlete to train the joints of the lower sagittal plane that consists of the ankle flexion/extension, knee flexion/extension, hip flexion/extension and the trunk flexion/extension. There are at least 43 muscles around these joints that are being developed, not to mention the muscle attachments and the central nervous system (CNS). Furthermore, if we were to complex the lift and add a clean and jerk to the movement, the athlete would then be able to develop the shoulder flexion/extension, elbow flexion/extension and the wrist flexion/extension. This increases the muscles exercised by 15, which would give a total 58 muscles around the joints of the sagittal plane being developed. Steel barbells do not support the lifting methods that permit this type of training.

The below lifting movements will be described and reference will be made to the above described new methods applied for both Force training and Speed training as they apply to each individual lifting movement. These new methods are directly related to the oscillatory movement of the ends of the flexible barbell when weighted means are affixed at or near the ends of the flexible barbell.

Force Training is the ability to activate muscle contraction against an opposing force that is applied through the flexible barbell. In amplitude speed training the muscles are trained to fire, or contract, with greater efficiency and/or greater speed through stimulation and training of the sensory receptors, or proprioceptors, located in the muscles and tendons with the muscles training against the resistive forces produced in the use of a flexible barbell.

Oscillatory training enhances sensory receptor stimulation wherein the ability of the sensory receptors to enhance stabilization of the muscle contractions is enhanced through the use of the oscillation characteristics of the flexible barbell.

Plyometric training improves muscle responsiveness, which results in improved muscle power, through the up-and-down or back-and-forth movements of the ends of the flexible barbell in which the muscles are rapidly lengthening more effectively followed by a more effective explosive muscle shortening movement that trains the targeted muscles to fire faster and produce a stronger muscle contraction.

The oscillatory movements of a flexible barbell promotes rehabilitation of the sensory receptors and facilitates the ability of the injured muscles to fire, or contract, more effectively following surgery, tear or sprain.

Many standard exercises can be enhanced with the flexible barbell including upper body exercises such as bench press, inclined bench press, shoulder press, bent over row and bicep curls; lower body exercises such as back squat, front squat, lunge walks, good mornings, dead lifts and box squats and total body explosive exercises such as power clean, hang clean, push jerk, push press, broad jump, vertical jump, split jump, Zercher push pull, power shrugs and high pulls.

Bench press for force training can be performed by loading the flexible barbell with a maximum load. The lifter takes the flexible barbell from the chest to lockout position, where the arms are fully extended, in a controlled manner and repeating. Bench press for speed training can be performed by loading the flexible barbell with a submaximal weight, such as 60% or less of one's body weight, and moving the flexible barbell rapidly in an up and down motion. Bench press for oscillatory training can be accomplished for speed and force movements. An example includes overloading the flexible barbell and holding the flexible barbell in a lockout position. The flexible barbell will naturally oscillate as a result of the upward forces applied to the approximate center of the flexible barbell during the initial bench press movement immediately preceding the lockout. The oscillating ends of the flexible bar force the sensory receptors, or proprioceptors, to be activated to balance or control the movement of the flexible barbell. This conditions the muscles and tendons in the joints to function together which enhances the athletic performance of the individual.

Inclined bench press for force training can be performed by loading the flexible barbell with a maximum load and taking the flexible barbell from chest to lockout position in a controlled manner repeatedly. Inclined bench press can be performed for speed training by loading the flexible barbell with a submaximal weight, such as 60% or less of one's body weight, and moving the flexible barbell in a rapid up and down motion. The flexible barbell can be used for oscillatory training by overloading the flexible barbell and holding in a lockout position while the flexible barbell oscillates as a result of the upward forces applied to the approximate center of the flexible barbell during the initial inclined bench press movement which immediately precedes the lockout. The oscillating ends of the flexible barbell force the sensory receptors to be activated to balance or control the movement of the flexible barbell as in the bench press.

Shoulder press for force training can be performed by loading the flexible barbell with a maximum load and moving the flexible barbell from between the chest and chin to a lockout position parallel to the body in a controlled manner and repeating. Shoulder press for speed training can be performed by loading the flexible barbell with a submaximal weight, such as 60% or less of one's body weight, and moving the flexible barbell rapidly in an up and down motion. The flexible barbell can be used for oscillatory training by overloading the flexible barbell and holding the flexible barbell in a lockout position while the flexible barbell oscillates as a result of the upward forces applied to the approximate center of the flexible barbell by the lifting motion preceding lockout.

Bent over row can be performed by loading the flexible barbell with a submaximal load and pulling the flexible barbell from the lockout position to the navel. The flexibility of the flexible barbell allows for force, speed and oscillatory training.

Tricep extensions may be performed by loading the flexible barbell with a submaximal load and extending the triceps from behind the head to over the head with arms fully extended and palms facing up. The flexibility of the flexible barbell permits force, speed and oscillatory training.

Bicep curls can be performed by loading the flexible barbell with submaximal weight and moving the flexible barbell from the hips to the upper chest in a standing curling movement with multiple repetitions. During the lower phase, or eccentric phase, of the movement the flexible barbell allows for a greater load to be transmitted to the bicep muscles due to the momentum gain from the downward movement of the moving weights which permits an enhanced stretching of the bicep muscle at approximately the end position of the lowering phase. In the enhanced stretch position the individual has placed the bicep muscle in a position such that in the following concentric lifting phase the bicep is able to be trained to contract faster due to the bicep muscle being stretched more effectively during the eccentric phase.

A back squat and front squat can be performed for force training by loading the flexible barbell with the maximal load and moving from a standing position to a squatted parallel position where the quadriceps are parallel to the ground and back to a standing position. In the back squat the flexible barbell is behind the neck whereas with front squat the flexible barbell is in front of the neck. The angle of the back is different for the two squats to maintain the weight over the centerline and feet. Because the flexible barbell bends in the center with the weights on each end of the flexible barbell bends across the back and shoulder of the lifter and therefore the load is not concentrated on the centerline of the body but instead are moved outwards towards the shoulders which allows the lifter to more effectively handle the load with the weight of the flexible barbell and weights being divided between each of the sides of the lifters shoulders as opposed to being concentrated on the centerline of the body. Speed training can be performed with the back squat by loading a submaximal load on the flexible barbell and moving in a rapid pace from standing to a squatting parallel position and back to a standing position. During the eccentric, or downward phase, of the squat the ends of the flexible barbell will bend downward to a greater degree as the lifter approaches the end of the downward movement. This continued loading of the muscles as a result of the downward movement of the loading of the muscles as a result of the downward movement of the ends of flexible barbell causes the sensory receptors in the muscles and tendons to be activated at an enhanced level resulting in more training and conditioning of the muscles involved in this squat exercise with one potential benefit being enhanced speed or contraction of the quads and hamstrings resulting in greater power movement by the lifter. The oscillatory training effect will take place naturally as the flexible barbell oscillates while the lifter performs the squat in a force or speed exercise.

Zercher squats for force training may be performed by loading the flexible barbell with maximal load and moving from a squatted position to a parallel position wherein the quadriceps are parallel to the ground back to the standing position while the flexible barbell is cradled in the cuffs of the elbow. The Zercher squat lowers the weight from the shoulders to mid-torso. As the lifter moves down during the squat and approaches the limit of the squat the ends of the flexible barbell will continue to move down which accentuates the load felt by the lifter thereby making the squat more difficult resulting in a greater ability for strengthening the glutes and hamstrings. Speed training can be performed with the Zercher squat by loading a submaximal load on the flexible barbell and moving in a rapid pace from standing to squatting parallel position and back to a standing position. The movements are more rapid than in force training and the loads transferred to the lifter's muscles are accentuated more than in the force Zercher squats with the benefit to the lifter being development of greater muscle strength targeted to the hamstrings and glutes. In addition, the fast pace of the speed training promotes sensory receptor stimulation and training with a potential for more effective use of the legs for sports specific uses. The oscillatory training effect will take place naturally as the flexible barbell oscillates while the lifter performs the Zercher squat in a force or speed manner.

Lunge walks can be performed by loading the flexible barbell on the lifters back, front shoulders or in the cuffs of the elbow followed by a forward or backward lunge step while assuring the shins are vertical and the quadriceps are parallel to the ground. Because the flexible barbell bends as the lifter approaches the end of the lunge movement the forces transferred to the lifter's muscles are enhanced thereby forcing the surrounding muscles to assist in stabilization making the lunge a more beneficial movement resulting in a greater ability to condition the targeted muscles and ancillary supporting muscles.

Good mornings can be performed by loading the flexible barbell on the lifters back followed by the lifter bending over while pushing their hips back until the desired amount of resistance is felt on the hamstrings, glutes and spinal erectors. As the lifter bends over and approaches the end of the bend the flexible barbell will continue to bend downwards forcing surrounding muscles to assist the body in stabilizing which results in conditioning of a greater number of muscles and surrounding tendons. As in a back squat this lift is made safer when using a flexible barbell since the flexible barbell bends in the center with weights on each end of the flexible barbell and the loads transferred to the outer parts of the body.

Dead lifts can be performed by loading submaximal to maximal weight on the flexible barbell and pulling the flexible barbell from the floor until the hips are locked in a standing position. The oscillation of the ends of the flexible barbell require the ancillary muscles to assist the body in stabilizing during this movement thereby increasing the conditioning benefit to the supporting ancillary muscles. As the lifter moves up from the standing position the weight of the flexible barbell will be increased due to the momentum of the weights flexing having momentum downward which the lifter has to encounter which results in greater conditioning due to the enhanced loads.

Box squats can be performed by using a box that is positioned at a height that allows the lifter to perform a parallel squat while sitting back on the box. The lifter loads the flexible barbell on the back with submaximal weight that enables the athlete to move into a speed training movement. The flexible barbell enables the lifter to more effectively develop the quads, glutes and hamstrings due to the fact that during speed training the ends of the flexible barbell continue to flex down following the sitting down of the lifter and with the lifter immediately exploding up from the sitting position with the ends of the flexible barbell moving down which places a greater load due to the moment which requires the lifter to exert more force as the lifter pushes up initially using the glutes followed by the quads.

The Power Clean can be performed as a ground base speed movement using the flexible barbell and submaximal weight. The Power Clean lift is benefitted more from a speed training standpoint than force training because of the flexible barbell's ability in use to stimulate the nervous system, which will help muscles respond and react faster. The flexible barbell aids in this process by overloading the muscle sensory system from a reactive, responsive and coordinated effort that can be transferred to the action of sport or to the action of lifting, jumping, running or movement in general.

The Hang Clean can be performed as a ground base speed movement using the flexible barbell and submaximal weight. The Hang Clean lift is benefitted more from a speed training standpoint than force training because of the flexible barbell's ability in use to stimulate the nervous system, which will help muscles respond and react faster. The flexible barbell aids in this process by overloading the muscle sensory system from a reactive, responsive and coordinated effort that can be transferred to the action of sport or to the action of lifting, jumping, running or movement in general.

The push jerk develops multi-joint explosive power and can be performed from a force movement or a speed movement. Oscillating movement is realized as the lifter stabilizes and controls the top end of the lift due to the flexing of the ends of the flexible barbell. The lifter presses the flexible barbell from the top of the chest to overhead in the frontal plane of the lifters body. This can also be done off of the back shoulders which builds explosive power as the lifters ankle, knee, hip and shoulder joint work in sequence to lock the flexible barbell out over the lifters head. The power generated in this movement should cause the athlete's feet to leave the floor.

The push press can be performed with both a force movement and a speed movement. Oscillating movement of the flexible barbell occurs as the lifter stabilizes and controls the top end of the lift due to the flexibility of the flexible barbell. The lifter presses the flexible barbell from the top of the chest to overhead in the frontal plane of the body. This can be done off of the back shoulders as well and builds explosive power as the lifters ankle, knee, hip and shoulder joints work in sequence to lock the flexible barbell out over the lifters head. The feet should remain in contact with the floor.

The broad jump, vertical jump and split jump are very difficult to accomplish safely with a standard steel barbell but due to the flexibility of the flexible barbell the lifter is able to move more freely and less rigidly as they perform broad jumps since the flexible barbell bends to absorb the force through the lower levers and then reapplies force as the lifter jumps.

The Zercher push pull benefits greatly from the flexible barbell. The flexible barbell gives the resistance of a push-pull movement that can develop balance and coordination in athletes, particularly football players. The flexible barbell sits in the cuff of the lifters elbows and as the lifter moves back and forth in a power position the ends of the flexible barbell move back and forth giving the sensation of a push-pull movement which is counter to the movement of the athlete.

Power shrugs or high pulls can be performed using a flexible barbell and are particularly preferred prior to performing a power clean or hang clean using a standard rigid steel barbell. The flexible barbell allows the overloading of the muscles due to the bending of the flexible barbell which provides for increased weight transfer to the affected muscles due to the momentum of the flexing flexible barbell which engages the sensory receptors resulting in the ability of the muscles to fire at a faster rate with resulting faster movement of a standard steel bar. The power shrug using the flexible barbell stimulates the muscles and sensory receptors in a way that they fire the nervous system which creates a muscle memory and when lifting a steel barbell the affected muscles remain actively firing and this condition helps transfer greater force to the steel barbell thereby enabling faster movement of the standard steel bar.

EXAMPLES Example A

A 2.28 M (90 inches) length of Schedule 40 extruded chlorinated polyvinyl chloride (CPVC) with an inside diameter (ID) of 38.1 mm (1.5 inches) and an outside diameter (OD) of 48.5 mm (1.91 inches) from IPEX America of Pineville, N.C. was used to prepare a bar suitable for accommodating at least 136 Kg (300 lbs) of total weight with the oscillation amplitude and oscillation frequency acceptable to the user when the hands are moving during the concentric and eccentric lifting phase of a bench press at a speed that may vary between 1 and 5 feet per second with the speed of the hands adjusted by the user to accommodate the training objectives with each hand positioned on each side of the centerline of the flexible barbell at a distance from 20.3 cm (8 inches) to 61 cm (24 inches) with 21.6 cm (8.5 inches) to 24.1 cm (9.5 inches) being the most common position for the hands from the flexible barbell's centerline.

The flexible barbell was coated with a thickness between 40 and 50 mils of Line-X® spray polyurea coating, XS-100, with a top coat of about 3 mils of Line-X®'s AspartX® black coating to give a tougher surface.

The expected deflection of each end of the flexible barbell with a defined amount of weight on each end of the flexible barbell using the equation for a simply supported beam where 2 concentrated loads are symmetrically applied. The two concentrated loads represent the weights applied to each end of the flexible barbell with the flexible barbell supported in the center using 2 hands spaced 21.6 cm (8.5 inches) on each side of the flexible barbells centerline. From Strength of Materials by Robert W Fitzgerald Copyright 1967 by Addison-Wesley Publishing Company, Inc.; pg 381 deflection at the end of the flexible barbell using the equation:

Deflection=[[P(weight on one end of bar=135 lbs)*[(Length of bar section: 2.28 M (90 inches)−43.2 cm (17 inches))/2]]/(24*EI) (with EI=216,256 for the construction of this bar)]*((3*90²)−(4*36.5²))=18″(45.72 cm) or converting to the angle from horizontal=35 degrees.

When performing a squat or a jump squat with the flexible barbell positioned behind the head and resting along the shoulders of the lifter, the flexible barbell is expected to respond acceptably with up to 227 Kg (500 lbs) of total weight.

A 137 cm (54 inches) long 7.62 cm (3 inch) inside diameter (ID) piece of clear 0.045″ thick heat shrink tubing, purchased as BuyHeatShrink® tubing(polyolefin) from Deerfield Beach, Fla. 33064 was applied over the outside surface of the CPVC tube following coating of the CPVC tubing with the LineX material and centered along the 2.28 M (90 inches) length of the CPVC tube. The shrink tubing had a shrink ratio of 2:1. The 137 cm (54 inches) long piece was selected due to the observation that 7.62 cm (3 inch) wide metal bar support brackets are provided on a standard barbell lifting rack which are about 54.6 cm (21.5 inches) from the centerline (CL) of the flexible barbell. The brackets are 7.62 cm (3 inch) wide and an extra length of 63.5 mm (2.5 inches) was added for safety suggest a length of 137 cm (54 inches) for the heat shrink tubing. The heat shrink tubing is a preferred option which provides benefits for the user of this flexible barbell. The heat shrink tubing provides a better gripping surface for one's hands when using the flexible barbell and increases slightly the OD of the Line-X® coated surface so that the 50.8 mm (2 inches) ID×15.24 cm (6 inches) long rack support pads will fit tight to the outside surface of the flexible barbell when installed at a distance of approximately 53.3 cm (21 inches) each side of the centerline of the flexible barbell. The rack support pads provide protection for the surface of the flexible barbell as it is place in and taken out of the rack support brackets on the lifting rack.

Three 2.2 M (86.75 inches) pultruded fiberglass reinforced plastic bars with dimensions of 9.525×31.75 mm (0.375×1.25 inches) were inserted in the flexible tube. The plastic bars were supplied by Glasforms, Inc. of San Jose, Calif. and each end of the plastic bars was beveled to prevent the ends from cutting into the CPVC inside wall. Each bar was a vinyl ester resin to better insure long flex life reinforced with 65% weight percent continuous fiberglass rovings.

The fiberglass bars were inserted into the cavity of the CPVC tube and a rubber end cap plug was inserted and glued into each end of the CPVC tube. The entire bar was coated with the Line-X® spray polyurethane/polyurea coating, XS-100. The rubber end caps were provided by Schacht/Pfister as model BB 21B 28.5 mm (1.125 inches). Krazy® superglue around the outside surface near the open end of the rubber end cap and using a twisting motion as the rubber end cap is pushed into the open ends of the CPVC tubing. Rubber end cap fits approximately 33.3 mm (1.312 inches) from the open end of the CPVC tubing into the cavity of the CPVC tubing thereby provided a finished length of flexible bar of about 2.3 M (90.75 inches).

Two 12.7 mm (0.5 inches) diameter holes were drilled, approximately 31.75 mm (1.25 inches) from the end of the rubber end plug, through the wall of the Line-X® coated CPVC tube and the wall of the rubber end cap plug for receiving a hitch pin with a diameter of 9.525 mm (0.375 inches)×63.5 mm (2.5 inches). The hitch pins were provided by Hillman and identified as a ‘Wire Lock’ pin square with product code 08236 77004. A 3.97 mm ( 5/32 inch) pilot hole was drilled before the 12.7 mm (0.5 inches) final hole was drilled. A template was used to mark the center of each hole with the holes positioned on opposite sides of the extruded flexible tube and each hole is 31.75 mm (1.25 inches) from the end of the tube with the holes positioned 180 degrees from each other. The open end of the rubber end plug that extends toward the interior of the CPVC tube from the hitch pin prevents the fiberglass bars from becoming wedged between the hitch pin and the inner wall of the tube thereby allowing the fiberglass bars to rotate freely inside the extruded flexible tubing.

Indicia, in the form of numbers, were stenciled onto the surface of the Line-X® coating before application of the heat shrink tubing. Starting with numbers 5.4 mm (1 inch) from each of the knurling line indicators, 21.6 cm (8.5 inches) from centerline of the tube, with numbers going from 1 to 18 in 5.4 mm (1 inch) increments. The numbers were 12.7 mm (0.5 inches) high and stenciled onto the surface of the Line-X® coating using a flexible plastic number stencil and a ‘Metallic Silver’ Sharpie® permanent marker. Logo labels containing Safety Caution information plus Instructions for using the bar, such as peel-n-stick labels, were applied to the surface of the flexible barbell as desired. The indicia and labels were placed prior to the heat shrink tubing being applied.

Wear pads can be installed if desired. Long tubular wear pads were installed by applying a liquid soap solution to the outside surface of the barbell and the inside surfaces of the 15.24 cm (6 inches) long flexible tubular wear pads and pushing the 15.24 cm (6 inches) long tubular wear pads from each end of the barbell to a position such that the 15.24 cm (6 inches) long tubular wear pad covers 15.24 cm (6 inches) of the end of the previously applied 137 cm (54 inches) long heat shrink tubing. The wear pad material was 50.8 mm (2 inches) ID extruded nylon with a braided material in the center for extra strength and was available as NEXBRAID® NT from NEXGEN Hose 120-32 from Dixie Rubber & Plastic, Inc. of Greenville, S.C. Double sided tape or an adhesive such as Krazy® superglue can be used to fix the position of the wear pads to the surface of the heat shrink tubing or LineX coated surface.

One or more ‘collars’ may be attached along the length of the flexible barbell at or near each end to position the disc weights along the length of the flexible barbell and/or to fix the position of the disc weights along the flexible barbell's length. A suitable collar is made by BFS (BiggerFasterStronger.com) and is identified as their item number 320095. This collar features a rubber type liner with a Velcro® strap webbing material used to secure the collar to the flexible barbell surface. The length of the collar is about 60.325 (2.375 inches).

After placing the weight on the flexible barbell the hitch pins are inserted through the 12.7 mm (0.5 inches) diameter holes previously drilled through the flexible barbell at each end of the flexible barbell.

Example B

A flexible barbell was prepared as in Example A with the exceptions listed below. A polypropylene (PP) extruded 38.1 mm (1.5 inches) Schedule 40 flexible tube used which is not as stiff a polymer as the CPVC material. The polypropylene polymer is hypothesized to provide a flexible barbell with greater long term use because of the increased tensile elongation properties of the polypropylene material as compared to polyvinylchloride (PVC) or CPVC. It may last longer in a flexing mode than PVC or CPVC. Also, the flexural modulus of the polypropylene (1.2−2.7×10⁵) is lower than PVC or CPVC (about 4×10⁵).

The flexible barbell was not coated with Line-X® spray polyurea due to the difficulty associated with getting materials to stick to the surface of polypropylene and the polypropylene material is hypothesized to be more abuse resistant than PVC or CPVC so this example was produced without a Line-X® coating. But since the LineX® polyurethane/polyurea coating totally encapsulates the tubing plus end cap plugs, a LineX spray material could be used.

The PP tubes were purchased as Enpure® natural Polypro Type II per ASTM D4101 pipe from IPEX America of Pineville, N.C. The tube had an ID of 39.837 mm (1.568 inches) and a wall thickness of 4.216 mm (0.166 inches).

Two different size bars were used due to the thickness of the tubing. Two pieces of fiberglass pultruded bars each 9.525 mm×31.75 mm×2.2 M (0.375×1.25×86.75 inches) and one piece of fiberglass pultruded bar at 7.92 mm (0.312 inches)×31.75 mm (1.25 inches)×2.2 M (86.75 inches) was used with the 7.92 mm (0.312 inches) thick piece placed between the two pieces of 9.525 mm (0.375 inches) thick bars. Together they fit easily into the cavity of the 38.1 mm (1.5 inches) polypropylene Schedule 40 pipe. The fiberglass bars had an isophthalic polyester resin with continuous fiberglass rovings with 65% weight percent fiberglass reinforcement. The ends of each fiberglass pultruded bars were beveled so that the sharp cut ends of the fiberglass bar would not damage the inside wall of the extruded flexible tube.

Example C

A flexible barbell was prepared as in Example A with the exceptions of the coating which was between 45 and 60 mils of Line-X® spray polyurea coating with a top coat of about 3 mils of Line-X®'s AspartX® black coating to give a tougher surface. This proved to be a heavier Line-X® coating than acceptable with the Olympic Disc weights being a little hard to slide onto the bar so the ‘new’ range of Line-X® coating is 40 to 50 mils with a nominal of 45 mils plus the 3 mils of AspartX® top coat.

The fiberglass bars were isophthalic polyester resin with 65% weight percent continuous fiberglass rovings.

Example D

A flexible barbell was prepared as in Example A with the exceptions of the tubing which was produced by Charlotte Pipe of Charlotte, N.C. and was otherwise the same. The flexible barbell was not coated with LineX™ but instead two layers of heat shrink tubing were used. The first heat shrink tubing was a 2.3 M (91 inches) long, 50.8 mm (2 inches) ID, 11.43 mm (0.45 inches) thick, black polyethylene with a shrink ration of 2:1 provided by Nelco Products—South; Clearwater, Fla. 33760 as Product ID: NP-221. The second heat shrink tubing was 137 cm (54 inches) long, 11.43 mm (0.45 inches) thick, 7.62 cm (3 inch) OD black polyolefin from BuyHeatShrink® tubing from Deerfield Beach, Fla. 33064.

The fiberglass bars were used as in Example A with all three bars being 9.525×31.75 mm (0.375×1.25 inches).

Example E

A 72″ long, 31.75 mm (1.25 inches) OD, ID =1 11/32″, Schd 40 PVC flexible tube used with one 9.525×31.75 mm (0.375×1.25 inches) fiberglass pultruded bar inside. The flexible barbell is designed to accommodate at least 200 lbs of total weight with the oscillation amplitude and oscillation frequency acceptable to the user when the hands are moving during the concentric and eccentric lifting phase at a speed that may vary between 1 and 5 feet per second with the speed of the hands adjusted by the user to accommodate the training objectives with each hand positioned on each side of the centerline of the flexible barbell at a distance from 20.3 cm (8 inches) to 61 cm (24 inches) with 21.6 cm (8.5 inches) to 24.1 cm (9.5 inches) being the most common position for the hands from the flexible barbell's centerline. This flexible barbell was not coated with Line-X® spray polyurea but a Line-X® coating with a thickness in the range of 60 to 75 mils with 3 mils of AspartX would be suitable for demonstration of the invention. Heat shrink tubing not used but it could have be used to demonstrate the invention.

One fiberglass bar, as described in Example B, was used wherein the bar had dimensions of 0.375″×31.75 mm (1.25 inches)×70.25″.

Also, two pieces of a 31.75 mm (1.25 inches) wide×70.25″ long piece of ‘blue’ flat foam material were used with one piece on each side of the fiberglass bar inside the PVC tube to reduce the noise that the fiberglass bar makes against the inside wall of the PVC tube when the flexible barbell is oscillating back and forth.

An embodiment containing 2 rectangular fiberglass bars, each ¼″ thick and ¾″ wide and 91⅜″ long will allow this flexible barbell to be used with a minimum weight on each end of about 25 pounds and a maximum weight on each end of the flexible barbell of about 90 pounds for a total maximum weight of 200 lbs. For uses where one would desire to put additional weight on each end of the flexible barbell, the cross-sectional area of the fiberglass composite elongated shape would need to be increased or possibly a composite tube with stiffness characteristics that would meet the increased stiffness needs. The defined preferred embodiment produces a flexible barbell with a stiffness that can be calculated by an engineer. A fiberglass bar with a width of 0.75″ and a thickness of 0.400″ would produce a fiberglass composite with a stiffness or bending resistance slightly more than twice the stiffness or bending resistance of the 2, 0.75″ wide×0.250″ thick as defined above. This alternative fiberglass shape would allow for a significant increase in the weight that could be placed on each end of the 96″ flexible barbell and still have correct amount of flexibility to be used in the various weightlifting exercises such as a squat where the user would move up and down at a certain rate or speed which would allow the ends of the weighted flexible barbell to move up and down and at a rate that would be in harmony with the rate of the up and down movement of the user thereby producing beneficial results by the enhancing the conditioning of the muscles used in performing a squat. Depending on the amount of weights placed on each end of the flexible barbell, the distance the weights are placed to the left and right from the center of the flexible barbell along the length of the flexible barbell and the speed at which the person moves up and down in performing the squat exercise, the ends of the flexible barbell will move up and down at a particular frequency. If there is too much weight on each end of the flexible barbell and/or the flexible barbell is not stiff enough, the ends of the flexible barbell will bend down too much and achieving an acceptable up and down movement of the ends of the flexible barbell to be in harmony with the up and down movement of the individual performing the barbell squat will not be possible. If the stiffness of the flexible bar is too low and the amount of weight on each end of the flexible barbell is too high, then effective movement of each end of the flexible barbell is not possible when performing an exercise such as a barbell squat. Such is the case with the described preferred embodiment where 225 pounds of weight is placed close to each end of the 96″ long flexible bar. Acceptable oscillation frequency and oscillation amplitude could not be obtained with 225 pounds of weight on each end of the flexible barbell. In this case, to perform the exercise effectively, the weight must be reduced and/or the cross-sectional area of the fiberglass composite must be increased which increases the bending resistance or stiffness of the flexible barbell.

An embodiment using 2 fiberglass pultruded rectangular bars that have a significantly greater cross-sectional area than in the above preferred embodiment permitting a greater amount of weight to be placed on each end of the flexible bar plus the surface of the flexible tube has been spray coated with a thermoset plastic material called a polyurethane/polyurea blend, similar to the spray on truck bed liners done by Line-X®, which provides enhanced surface durability plus the texture of the spray applied polyurea is slightly rough providing a good gripping surface.

Example F

A 96″ long, 38.1 mm (1.5 inches) PVC schedule 40 extruded pipe manufactured by Silver-Line® Plastics; Asheville, N.C. 28804 which has an approximate OD of 1.91 inches and an ID of 1 9/16″ was used. The entire outer surface was spray coated using Line-X® standard black thermoset polyurethane/polyurea spray coating. The coating is applied in two passes and the approximate total thickness of polyurea applied is about 25 mils. A 38.1 mm (1.5 inches) plastic mechanical pipe plug from Oatey® of Cleveland, Ohio was inserted to provide a finished length of flexible elongated tubing plus 38.1 mm (1.5 inches) plastic mechanical pipe plug affixed inside each end of the 38.1 mm (1.5 inches) PVC tube was 97.75″. The wing nut of this Oatey pipe plug adds about ⅞″ to the length of each end of the 38.1 mm (1.5 inches) PVC extruded tube.

Two 94″ long fiberglass pultruded rectangular bars with dimensions of 9.525 mm×31.75 mm×2388 mm (0.375×1.25 inches wide×94 inch) were inserted in the tube. This shape had a flexural modulus of approximately 5-6 million psi.

A 4″ to 12″ long cylindrical plastic tube, from Keeney Mfg. of Newington, Conn., in which the flange on one end has been cut off is slipped over the 2 pieces of fiberglass rectangular bars in order to minimize any abrasive effects of the cut ends of the fiberglass rectangular bars from abrading the inside surface of the PVC tube. Over the outer end of each of the plastic tube, a piece of duct tape is applied to fix the position of the plastic tube at each end of the fiberglass bars. The outside diameter of the plastic cylinder is smaller than the inside diameter of the PVC tube permitting the plastic tube to be fully contained inside the finished flexible barbell.

A standard black conventional compression cylindrical device used routinely in strength and conditioning facilities were placed over each end of the 38.1 mm (1.5 inches) PVC tube to fix the position of the disc weights that were slid onto each end of the flexible barbell. Once the appropriate weights were slipped onto the flexible barbell an additional standard black conventional compression cylindrical device was slipped onto each end and tightened to prevent the weights from sliding off Alternately, Velcro® strapping such as ‘hook’ and ‘loop’ 25.4 mm (1 inch) wide strapping could be used to wrap around the flexible barbell on the outside and inside of the circular weights that are placed on each end of the flexible barbell.

A wire lock pin, round or square would suffice, was used near each end of the flexible barbell as a safety feature to insure that any weights placed on the flexible barbell do not slip off during use. As an example a 13/64″ diameter round hole would be drilled through the center and both walls of the PVC tube about 31.75 mm (1.25 inches) from each end of the PVC tube. This is sufficient distance from the ends to still allow the compression plug to be used in each end of the tube. After the hole is drilled, a wire lock pin with dimensions of 9.525 mm (0.375 inches)×2½″ was inserted through the hole and the square wire attachment slipped over the free end of the pin to insure that the pin did not fall out.

This embodiment was able to function acceptably with up to 225 lbs of weight placed on each end of the flexible barbell. Three of the fiberglass bars with dimensions of 9.525×31.75 mm (0.375×1.25 inches) is preferred at this weight which significantly improves the responsiveness although a weight of 135 lbs on each end of the flexible barbell would make speed training more effective.

Example G

A flexible dumbbell consisting of a 20″ long piece of ¾″ flexible PVC tubing from Jain Irrigation, Ontario, CA with a flexural modulus of about 5,000 psi and inside the flexible PVC tubing is a 19⅝″ long pultruded rectangular bar (0.1875″×0.500″×19⅝″) with a flexural modulus of 5,500,000 psi with a 10 lb standard disc weight with a 25.4 mm (1 inch) diameter hole in the center on each end of the flexible PVC tubing 7.75″ from the center of the tube with a rubber end cap from Schacht Pfister of Huntington, Ind. fixed on each end of the flexible PVC tube using Krazy superglue with a metal hose clamp fixed in position between the rubber end cap and the 10 lb disc weight. The maximum deflection was measured in the center of the flexible PVC tube by lifting up on the center of the flexible PVC tube until the 10 lb weights just started to come off of the floor and a deflection of 1.3″ was measured. The angle of deflection, as measured by dividing the 1.3″ deflection by the length, 7.75″, equaled 9.5 degrees. The feel of the dumbbell was good when performing bicep curls and the oscillation of the ends of the dumbbell was controlled.

This dumbbell prototype was meant to simulate a dumbbell in which the weights on each would not be removable. The use of the metal hose clamps assured that the weights did not come off of the ends. 25.4 mm (1 inch) wide electrical tape was wrapped around the circumference of the flexible PVC tube just inside the 10 lb weight which prevented the weight from moving toward the center of the dumbbell.

Example H

A 2.28 M (90 inches) length of Endot Industries, Inc. of New Jersey ‘HDPE’ (high density polyethylene) thermoplastic tubing with an inside diameter (ID) of 1.54″ and an outside diameter (OD) of 1.9″ with a flexural modulus of 80,000 psi was used to prepare a flexible bar to accommodate up to 136 Kg (300 lbs) of total weight with the oscillation amplitude and oscillation frequency acceptable to the user when the hands are moving during the concentric and eccentric lifting phase of a bench press at a speed that may vary between 1 and 5 feet per second with the speed of the hands adjusted by the user to accommodate the training objectives with each hand positioned on each side of the centerline of the flexible barbell at a distance from 20.3 cm (8 inches) to 61 cm (24 inches) with 21.6 cm (8.5 inches) to 24.1 cm (9.5 inches) being the most common position for the hands from the flexible barbell's centerline. HDPE is expected to give longer flex life to the flexible barbell over that available with CPVC tubing due to the significantly higher elongation properties.

The flexible barbell was coated with a thickness between 35 and 45 mils of Line-X® spray 100% polyurea coating, XS-350, with a top coat of about 3 mils of Line-X®'s AspartX® black coating to give a tougher surface.

Following coating with LineX, 12.7 mm (0.5 inches) diameter holes were drilled through each end of the bar 31.75 mm (1.25 inches) from the end of the rubber end cap plug. Then the labels plus indicia were applied to the center of the bar over the LineX coating. Next, the heat shrink tubing at a length of 44″ was applied. Then the 15.24 cm (6 inches) long wear pads were applied with the inside end of each wear pad positioned 53.3 cm (21 inches) from the centerline of the bar and covering about 25.4 mm (1 inch) of heat shrink tubing. Double sided tape with a liquid activator from Golfsmith International of Austin Tex., similar to the materials used in re-gripping golf club grips was applied to the surface of the LineX coating prior to sliding the wear pads onto the bar to fix the position of the wear pads. Finally, the hitch pins were applied to each end of the flexible barbell.

To give this flexible barbell sufficient stiffness (EI) to function effectively as a 136 Kg (300 lbs) rated barbell, the fiberglass shapes inside the HDPE tubing consisted of one fiberglass pultruded bar, 9.525 mm×31.75 mm×2.2 M (0.375×1.25×86.75 inches) and one fiberglass pultruded solid round rod, 0.812″ diameter×2.2 M (86.75 inches) long, which together with the HDPE tube plus the LineX coating gave a stiffness of approximately 200,000 lbs-in².

Example I

A 2.28 M (90 inches) long preferred embodiment using a 2.28 M (90 inches) long 38.1 mm (1.5 inches) CPVC schedule 40 tube and coated with a LineX XS-350 coating to a thickness of about 11.43 mm (0.45 inches) with 3 fiberglass bars inside the CPVC with each bar being 9.525×31.75 mm×2.2 M (0.375×1.25×86.75 inches) long with a flexural modulus of about 26,900,000 kg/M² (5,500,000 psi) for the fiberglass bars and a single lifting force applied in approximately the center of the barbell would result in a ‘static deflection’ at the ends of about 5 inches with one (1) 45 lb iron disc weight placed on each end of the barbell and a static deflection of about 10 inches with two (2) 45 lb iron disc weights placed on each end of the barbell. The calculated barbell stiffness (EI) for the above flexible barbell construction is about 1,000,000 kg/M² (215,000 lbs-in²) with about 571,000 kg/M² (117,000 lb-in²) for the CPVC tube; 146,000 kg/M² (30,000 lb-in²) for each of the 3 fiberglass bars and about 36,000 kg/M² (7,400 lb-in²) for the LineX XS-350 coating. The deviation from linearity, D, during use at maximum bend of the bar will be greater that the static deflection with this maximum amount dependent on the strength of the athlete and the speed of movement of the barbell. Practical knowledge of the bending characteristics of the materials used to construct a flexible barbell suggests that the barbell will become unsafe if the acute angle α becomes greater than 90 degrees during use.

Comparative Example

2.28 M (90 inches) Acrylonitrile butadiene (ABS) 38.1 mm (1.5 inches) Schedule 40 flexible tube Produced by IPEX America of Pineville, N.C. was used. The tube had an ID of 42.26 mm (1.664 inches) and a wall thickness of 3 mm (0.118 inches). The bar was coated with between 45 and 60 mils of Line-X® spray polyurea coating with a top coat of about 3 mils of Line-X®'s AspartX® black coating plus a 3 mil top coat of AspartX® black coating to give a tougher surface. One layer of heat shrink tubing, purchased as BuyHeatShrink® from Deerfield Beach, Fla. 33064, was applied using several pieces over the approximate center 137 cm (54 inches) to provide. The heat shrink tubing was 11.43 mm (0.45 inches) thick, clear color with a 7.62 cm (3 inch) OD and a 2:1 shrink ratio. Length 137 cm (54 inches) with 3 pieces used to give the 137 cm (54 inches) and positioned in the center of the tubing. Three 2.2 M (86.75 inches) fiberglass bars, with beveled edges were used in the ABS. The fiberglass bars had cross-sectional dimensions of 9.525×31.75 mm (0.375×1.25 inches) with isophthalic polyester resin and 65 wt % continuous fiberglass rovings. Body Bar, Inc. end caps ACO #21 used as a plug and applied into each end of the ABS tubing applying Krazy® superglue around the outside surface near the open end of the rubber end cap and using a twisting motion as the rubber end cap is pushed into the open ends of the ABS tubing. Rubber end cap fits approximately 33.3 mm (1.312 inches) from the open end of the ABS tubing into the cavity of the ABS tubing to provide a finished length of 2.3 M (90.75 inches). Wire lock pins were installed as described above.

This flexible barbell failed in use. A minimal amount of weight was on the flexible barbell with about 22.7 Kg (50 lbs.) on each end but the method of use was jump squats which produced large oscillation amplitudes that resulted in the tube fracturing. The amplitudes were less than those which occur when the ends of the flexible barbell result in the ends of the flexible barbell, in a bent condition, being parallel to each other. The failure mode was a ‘clean’ fracture around the circumference of the ABS tube with the location about 15.24 cm (6 inches) from the centerline of the flexible barbell. This failure indicates that ABS in this flexural bending application is not a suitable polymer. It would appear that the ABS material simply does not have enough tensile elongation. The tensile elongation of PVC and CPVC is roughly twice that of ABS.

The evaluation of this flexible barbell using the ABS pipe manufactured by IPEX America confirms that this standard extruded pipe ABS formulation does not have sufficient flexibility to function as an acceptable flexible barbell. It is possible to add a greater percentage of the polybutadiene rubber component of the ABS material formulation such that this material might be able to be used to extruded a flexible tube that could function successfully in this application.

The invention has been described with specific reference to exemplary embodiments without limit thereto. One of skill in the art would realize additional improvements and embodiments which are not specifically set forth but which are within the scope of the invention as set forth in the claims appended hereto. 

What is claimed is:
 1. A barbell system for enhancing weight lifting exercises comprising: a elongated barbell comprising a first end and a second end; weights for placing symmetrically on said first end and said second end; and a locking device for securing said weights to said bar wherein said locking device comprises: a split collar capable of receiving said elongated bar therein; and a locking device capable of drawing said split collar into engaging relationship with said elongated barbell.
 2. The barbell system for enhancing weight lifting exercises of claim 1 wherein said split collar comprises thermoplastic rubber.
 3. The barbell system for enhancing weight lifting exercises of claim 1 wherein said split collar has a durometer of 65 to 100 Shore A.
 4. The barbell system for enhancing weight lifting exercises of claim 1 wherein said split collar has a contoured surface on an interior diameter.
 5. The barbell system for enhancing weight lifting exercises of claim 4 wherein said contoured surface has a contour depth of at least 0.1 mm to no more than 0.5 mm.
 6. The barbell system for enhancing weight lifting exercises of claim 1 wherein said split collar has at least one raised edge on the outside diameter surface.
 7. The barbell system for enhancing weight lifting exercises of claim 6 wherein said raised edge is at least 1 mm to no more than 4 mm in height.
 8. The barbell system for enhancing weight lifting exercises of claim 1 wherein said locking device comprises a strap.
 9. The barbell system for enhancing weight lifting exercises of claim 8 wherein said strap comprises nylon.
 10. The barbell system for enhancing weight lifting exercises of claim 8 wherein said strap is wrapped at least partially around said split collar.
 11. The barbell system for enhancing weight lifting exercises of claim 8 wherein said strap comprises a first end attached to a ring.
 12. The barbell system for enhancing weight lifting exercises of claim 11 wherein said strap comprises a second end reversibly receivable by said ring.
 13. The barbell system for enhancing weight lifting exercises of claim 1 wherein said strap comprises a closure element.
 14. The barbell system for enhancing weight lifting exercises of claim 13 wherein said closure element comprises a hook and loop closure.
 15. The barbell system for enhancing weight lifting exercises of claim 1 wherein said strap is secured to said split collar.
 16. The barbell system for enhancing weight lifting exercises of claim 1 wherein said locking device comprises a ring.
 17. The barbell system for enhancing weight lifting exercises of claim 16 wherein said locking device comprises a pivoting latch.
 18. The barbell system for enhancing weight lifting exercises of claim 17 wherein said ring is attached to said pivoting latch.
 19. The barbell system for enhancing weight lifting exercises of claim 18 wherein said ring reversibly engages with a fixed attachment.
 20. The barbell system for enhancing weight lifting exercises of claim 1 wherein said elongated barbell is a flexible barbell.
 21. The barbell system for enhancing weight lifting exercises of claim 20 wherein said flexible barbell comprises: an elongated shape comprising a center and ends; and at least one flexible bar in said elongated shape wherein said flexible bar has a minor axis and a major axis and is capable of rotating in said elongated shape.
 22. The barbell system for enhancing weight lifting exercises of claim 21 wherein said elongated shape bends relative to a tangent to said center in response to said center of said flexible barbell being moved.
 23. The barbell system for enhancing weight lifting exercises of claim 21 wherein said flexible bar is rectangular.
 24. The barbell system for enhancing weight lifting exercises of claim 21 further comprising at least one flexible rod.
 25. The barbell system for enhancing weight lifting exercises of claim 24 wherein said flexible rod is round.
 26. The barbell system for enhancing weight lifting exercises of claim 21 wherein said flexible bar has a hollow cavity which extends the entire length of said flexible bar.
 27. The barbell system for enhancing weight lifting exercises of claim 21 wherein said flexible bar comprise a fiber reinforced resin.
 28. The barbell system for enhancing weight lifting exercises of claim 27 wherein said flexible bar comprises fiberglass.
 29. The barbell system for enhancing weight lifting exercises of claim 27 wherein said flexible bar comprises carbon.
 30. The barbell system for enhancing weight lifting exercises of claim 21 comprising multiple flexible bars.
 31. The barbell system for enhancing weight lifting exercises of claim 30 comprising at least 2 to no more than 3 flexible bars.
 32. The barbell system for enhancing weight lifting exercises of claim 1 wherein said elongated barbell has a length of at least 25.4 cm to 2.4 M.
 33. The barbell system for enhancing weight lifting exercises of claim 32 wherein said length is at least 1.5 M up to 2.4 M.
 34. The barbell system for enhancing weight lifting exercises of claim 21 wherein said elongated shape is formed from a fiber reinforced thermoplastic and thermoset resin.
 35. The barbell system for enhancing weight lifting exercises of claim 21 wherein said elongated shape is extruded using either a reinforced or unreinforced thermoplastic resin material.
 36. The barbell system for enhancing weight lifting exercises of claim 1 wherein said elongated barbell has a stiffness of at least 1,000 lbs-in² to no more than 500,000 lbs-in².
 37. The barbell system for enhancing weight lifting exercises of claim 36 wherein said elongated barbell has a stiffness of at least 30,000 lbs-in² to no more than 350,000 lbs-in².
 38. The barbell system for enhancing weight lifting exercises of claim 1 wherein said weights are at least 1.13 Kg to no more than 227 Kg.
 39. The barbell system for enhancing weight lifting exercises of claim 38 wherein said elongated shape bends in a static mode when supported in the center of the bar to the extent that said ends deflect at least 12.7 mm to no more than a 45 degree acute angle relative from said tangent to said center.
 40. The barbell system for enhancing weight lifting exercises of claim 39 wherein said elongated shape bends in a static mode when supported in the center of the bar to the extent that said ends deflect at least 63.5 mm.
 41. The barbell system for enhancing weight lifting exercises of claim 1 wherein said elongated barbell comprises a fiber reinforced resin.
 42. The barbell system for enhancing weight lifting exercises of claim 41 wherein said resin is selected from the group consisting of vinyl ester thermoset, isophthalic polyester thermoset, epoxy thermoset, polyurethane thermoset, polyvinyl chloride, polypropylene, high density polyethylene, thermoplastic rubber, and chlorinated polyvinyl chloride.
 43. The barbell system for enhancing weight lifting exercises of claim 1 further comprising a surface treatment on at least a portion of said elongated barbell.
 44. The barbell system for enhancing weight lifting exercises of claim 43 wherein said surface treatment is selected from an applied coating and a wrap.
 45. The barbell system for enhancing weight lifting exercises of claim 44 wherein said wrap comprises a tape.
 46. The barbell system for enhancing weight lifting exercises of claim 44 wherein said applied coating comprises a polymeric material.
 47. The barbell system for enhancing weight lifting exercises of claim 46 wherein said applied coating has a flexural modulus of at least 15,000 psi.
 48. The barbell system for enhancing weight lifting exercises of claim 46 wherein said polymeric material has a thickness of at least 15 mils to no more than 250 mils.
 49. The barbell system for enhancing weight lifting exercises of claim 48 wherein said polymeric material has a thickness no more than 90 mils. 